Da Schneib is an amateur astronomer. Perhaps some of my musings will be helpful.
Tasco doesn't make anything you should waste your money on.
The biggest part of the price depends on whether you want to just look, or take pictures. Just looking isn't very expensive; taking pictures costs a lot. I'm $50k or more into my habit, and doing relatively well. If I just wanted to look, I'd have stopped at well under $10k. And that would be the Cadillac, nay, the Rolls Royce, setup for it. The Chevy will run you around $2k or less. You can get a Yugo for a few hundred bucks. But don't start there; start with binoculars and good books. You don't have to drop all the money at one time; you can spread it out a bit, over several years as you decide what precisely you want to do.
There are three major classes of telescope:
Refractor: this is the common conception of a telescope. In its simplest incarnation, it's two lenses; one to gather the light, and one to focus and magnify the image for your eye. Basically it's a long tube with a lens at each end. The big one farthest from you is called the "objective;" the little one you put your eye up to is called the "eyepiece." These are both the most and least expensive telescopes. The least expensive ones are little more than toys, if that, basically incapable of any serious observing and generally consigned to the attic after a few neck-wrenching frustrating sessions of not seeing much by their unfortunate victims. The most expensive are some of the finest optical instruments on Earth, and the most expensive per aperture of all types of telescope. Special glass is used to create the finest possible image. They have a great deal in common with the huge lenses you see on the sides of football fields, both in terms of price and in terms of performance.
Reflector: this is a telescope that uses a mirror as its objective; in its simplest incarnation, merely a large, concave mirror at the bottom of a tube. If it's a large mirror, you can just point it up at the sky and stick your head up there; because the mirror is curved, you won't see yourself, you'll see a magnified image of the stars. Herschel, among others, used a telescope like this. The ones you're most likely to find available today are Newtonian reflectors; these put a small mirror in the middle of the tube, at the right distance to get all the light cone from the big mirror at the bottom of the tube, and bounce the tip of the light cone out the side of the telescope. You can put an eyepiece there, and magnify the image and make it the right size for your pupil. A man named John Dobson invented a way to mount these telescopes that is very inexpensive: you make a box with two half-circles cut out of opposite sides, and put two disks on the sides of the tube, and a lazy-susan type bearing on the bottom of the box. These are called "Dobsonian" in his honor. Dobsonians are the least expensive per aperture. In these telescopes, the big mirror is called the "primary" and the little one the "secondary." An eyepiece is still an eyepiece. There are other types of reflectors; there is the Cassegrainian, which has a hole drilled in the center of it so that a secondary can reflect the light from the primary down through the hole. It turns out that the outside of the mirror is the most important, so this works fine. These are the most common types of amateur reflectors; overwhelmingly so. There are a few folded designs, or ones that use mirrors with novel shapes, to avoid the central obstruction that is a practically universal feature of reflectors; I've only seen a few.
Catadioptric: These telescopes combine reflective and refractive elements. The Schmidt-Cassegrain Telescope (SCT) is by far the most common; these use a primary and secondary and a hole in the middle of the primary like a Cassegrainian, but they also use a corrector plate at the front of the tube. This is by far the most common amateur telescope. Significant numbers of these telescopes have been build and sold by Celestron and Meade. They are medium in expense per aperture between the Dobsonian Newtonian and the high-end refractor. They are the lightest and smallest telescope per aperture. They are also for technical reasons the most flexible type of telescope; their design maximizes something called "back focus" that you'll find out all about if you get into astrophotography. Furthermore, in addition to inherent flexibility due to their design, they have more different adapters and field flatteners and focal reducers and other doo-dads available for them than Carter has little liver pills.
Each type has advantages and drawbacks.
The refractors are the most expensive, but capable of the best images per aperture. They excel at lunar and planetary astronomy, where the object is relatively bright, so optical quality is the most important parameter rather than light-gathering, which depends on aperture. They are also excellent for photography, for some of the same reasons. With a big one, 5 or 6 inches, you can do good deep-sky astronomy as well, but you can spend more on one like that than on a good used car. For photography, you'll also need a good mount; I'll get into that in a bit. They'll need a medium to good mount; they are generally long, so they have a moment arm. These are probably the last type of telescope you'll want to buy, unless you get bit bad by the astronomy bug.
The reflectors are generally the least expensive per aperture, and excel at deep-sky visual astronomy because they are generally of large aperture (10 or 12 inches is not uncommon, for considerably less money than a refractor of lesser aperture. If you want to go hunting for faint remote galaxies, and planetary nebulae, this is your telescope. But they are remarkably lousy at astrophotography; they are very long, and thus have a long moment arm and are difficult to mount for photography, requiring the most expensive mounts, and they sorely lack all-important back focus and major modifications are needed to allow photography with them, which generally make them difficult or impossible to use for visual astronomy. Still, if all you want to do is look, this is probably the way you want to go.
The catadioptrics are excellent for photography, very good for planetary, and very good for deep-sky. Their long back focus and short tube make them easy to adapt to almost any imaginable camera and easy to mount on cheap to medium mounts for passable photography results. They give optical results that in the best examples are easily the equal of the deep sky that a Newtonian can do. Because you can go to bigger apertures for reasonable money, you can get excellent planetary views rivalling anything even a big refractor can do; remember, "big" for a refractor means 5-6", whereas "big" for a cat means 12-15". Although the image from the big refractor is technically "cleaner," it's possible with careful adjustment and careful selection of accessories to rival or beat what any smaller telescope can do. Only a refractor in the same size class as a big cat can beat the cat, and that's not a car's worth of expense- more like a house. And you'll need to build a permanent observatory for a big refractor, you're not putting it in your car and taking it anywhere unless you've got a semi trailer and a forklift handy. You can take a Dob apart for transport, if it won't fit; it's relatively easy to take them apart and put them together.
So my advice is, if you're sure you just want to look get a Dob; if you're not sure and might want to take pictures, start with an SCT.
One saying of note is that in all optics of acceptable quality, aperture ALWAYS wins. This must be taken with a grain of salt; if you just want to look, this is inarguably true. On the other hand, if you want to take pictures, a big refractor of the highest quality may well beat a medium SCT of good quality. It also depends what you want to take pictures of; the refractor will usually beat the SCT for planets or the Moon, but the SCT may well beat the refractor for galaxies and planetary nebulae. The SCT will not take as wide a field generally, so the refractor may be best for diffuse nebulae. On the other hand, for smaller diffuse nebulae, the SCT may show more detail because of its larger aperture. So if you want to take pictures, consider what you want to take pictures OF.
Now, for mountings.
If you buy one of the popular package deal SCTs, they often come with a mount. It's generally OK for visual observing, but not very good if even usable at all for photography. It has been said that you need three things for astrophotograpy: a good mount; no, a REALLY good mount; and lots of patience. Dob mountings are essentially unusable for astrophotography; they can be adapted for it, but it's a major PITA. A mount that will work well for a medium SCT will not work well for a big refractor. If you want to take pictures, you will need a mount that will cost as much as your telescope or more.
There are two general types of mountings: altazimuth, which is a truncation of altitude-azimuth, in which one axis points directly overhead and allows rotation like a lazy susan, and the other points in a direction determined by the first and allows the telescope to be adjusted in altitude; and equatorial, in which one axis points at the celestial North Pole, very close to the star Polaris, and the other allows the telescope to be adjusted in Right Ascension, which is what astronomers call longitude on the sky. The most common types of equatorial mounts are the German equatorial (GEM) and the fork mount; this last is common on Meade and Celestron SCTs sold as packages, and is generally sold low-end as an altazimuth mount, where the base of the fork turns in azimuth; to make it equatorial, you get an "equatorial wedge" (generally an extra-cost option) that permits the azimuth axis to be pointed at the pole. Many relatively good astrophotographs are taken with small to medium SCTs using fork mounts and equatorial wedges. However, if you want to do serious astrophotography with a medium to large SCT or a large refractor, you'll want a GEM, and a good one.
Finally a few things to set your expectations:
1. You will almost certainly not see colors in anything but planets. A few stars are colored, but you'll grow bored with that relatively quickly. From a very, very dark site, with a very, very large telescope, there are perhaps two or three nebulae in the entire sky in which you will see color. Otherwise, it's pretty much all going to look black-and-white to you. On the other hand, you can easily take photographs, with only a camera lens, that will show color in nebulae all over the sky. This is because of the fact that the camera shutter will remain open for minutes or hours, but your eye takes a "picture" about fifteen times a second. There's more to it; ask if you are curious. Human scotopic vision and dark adaptation are interesting subjects.
2. With a decent telescope, you'll be able to see the Cassini Division in the rings of Saturn. You'll be able to see craters on the Moon, and mountains, and other small features. You'll be able to see bands on Jupiter; if you're lucky, you'll catch a few glimpses of the Great Straw Colored Spot (it's not red anymore since Schoemaker-Levy hit it). You'll be able to see Mars' polar icecaps; if you're lucky, you'll catch a few glimpses of the surface features on Mars. There are perhaps a hundred open clusters, and ten or twenty globular clusters, that are of note. There are probably hundreds or thousands of galaxies, of which perhaps fifty or less are notable. To see more, you'll need three things:
a. An excellent telescope.
b. A very dark sky.
c. Good seeing.
3. Seeing is very important for getting detailed views. This concerns how still the atmosphere is, and how clear it is. The atmosphere is constantly moving; and because there's so much of it between you and the things you're looking at, when it moves, it changes its refractive index. The more magnification you use, the more important that will be. It can make views of planets and the Moon dance around in the eyepiece; it can do the same thing to stars. One good way to gauge the seeing is just to wait until your eyes are dark-adapted and then look up. If the stars are twinkling a lot, the seeing isn't good; if the planets are twinkling, you're hosed. If the bright stars are still, and only the dimmer ones twinkle, the seeing is good. If pretty much every star you can see doesn't twinkle, then the seeing is excellent.
Most important of all, HAVE FUN! That's what it's really all about.
