Depends on how you define regulation. I don't call oversight of an industry and outlawing fraudulent business practices to be regulation.
I define it as actions of the government above and beyond its proper role of defending rights against those who initiate force and fraud. That is where I would guess you put the line for over-regulation.
The problem with the libertarian idea of regulation (preventing the initiation of force or fraud) is in defining when the initiation of force or fraud occurs. For example, is there initiation of force or fraud where there is a massive inequality of bargaining power? What about collusion among firms?
Scenario A:
Bob is a regular guy. He has an average unskilled job, not much savings, no health insurance. He gets cancer. He misses some time off work, so they fire him. There are other people who can easily fill his shoes, and the employer wants to make sure that someone is there day to day so they hire someone healthy.
Bob now uses his savings (and more) to pay for medical treatment as he has no desire to die. The hospital gives him a bill, which he cannot pay. He still needs treatment, and the hospital won't give it to him without cash up front and paying the old invoice. Bob tries to get a loan at a bank, but he is a poor credit risk due to the cancer and no job, so he is denied.
Bob, in desperation, sees Tony, the last chance loan guy. Tony agrees to lend him money for treatment at 10% interest per month. He tells Bob that if he doesn't pay, then he will send Guido to inflict bodily harm. Bob understands this, but needs the money for treatment or he will die. So he agrees with Tony to get the money.
Bob gets the treatment, but doesn't get a job and can't pay back Tony. Guido breaks 3 of Bob's ribs.
Where, if anywhere, is the 'initiation of force or fraud' in this scenario? Where would an ideal Libertarian government step in, if at all?
Scenario 'B'
The market for gas is controlled by a relatively small number of market players. For the sake of argument, let's say that there are 5 major companies that control gas stations in a particular city. No matter where you buy gas, you are buying from one of the 5.
One day some bright young executive fresh out of MBA school runs some numbers and realizes that if the price of gas were 25 cents higher, they would make a lot more money. He is also bright enough to know that his company can't be the only one to raise the price of gas, as people will just buy it cheaper from one of the other 4 companies. So, he gets together with other bright young executives from the other 4 companies and proposes that they all agree to raise the price together, which will mean a rise in profits for all. The others all agree, and the next thing you know gas is 25 cents higher.
The consumers are all upset, but they need gas so they pay the extra 25 cents to get it.
Where, if anywhere, is the 'initiation of force or fraud' in this scenario? Where would an ideal Libertarian government step in, if at all?