The Twilight books have the real town of Forks, Washington, as their major setting. My book Hunter’s Moon and its forthcoming sequels have Wellsboro, Pennsylvania, as theirs.
Authors who set their books in real places usually (hopefully!) do at least some research on those locations if they’re not already familiar with them. I haven’t had the chance to visit Wellsboro yet*—I really want to, though—but of course online research is pretty darn helpful.
Sarah Awa lives in Ohio with two hairy guys and writes books about werewolves.