Third on the Elvis Cole series, though lately his last pages (and I mean literally the last pages) have become annoyingly maudlin. Monkey's Raincoat was the first and won and Edgar, I think. Probably the closest to a whodunnit as any in the series.
I also recommend the Robicheaux series by James Lee Burke. You can read them in any order but will gain more by starting at the beginning. (Sorry I can't remember what that is; it's been a long time and I haven't read them all).
Tony Hillerman's books are occasionally excellent, too, and give a marvelous flavor of the American Southwest and Native-American (particularly Navajo) society.
Patricia Cornwell's early works are worth reading, too, though her later works became screeds. In particular, Postmortem is a must read. It won the Edgar, the Creasey, the Anthony, the Macavity, and the Prix du Roman d'Adventure.
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And now a request: I am looking to acquire a few good whodunnits, but I haven't kept up with the field. In particular, I would like some that provide good atmospherics for the countrysides of Scotland and/or Ireland. I tend to enjoy something that--while still relatively light--is perhaps a bit melancholic.
If that made sense, can anyone recommend some authors or titles?
Thanks