The Morgue and Me by John C. Ford. I first picked this one up because it was written by a guy who grew up in Birmingham, and it is set in Petoskey. But I was hooked right from the beginning -- great narrative voice, intriguing mystery, interesting characters, and, of course, a good setting! If you like wry narrators and a little bit of noir in your mysteries, give this one a try.
UPDATE: The Morgue and Me was nominated for an Edgar Award in the YA category!