I spotted this book, A Literary Guide to Flannery O'Connor's Georgia, and thought it looked interesting. From the UGA Press website:
"The guide describes such places as O'Connor's childhood home in Savannah; the Governor's Mansion, Cline House, and Central State Hospital in Milledgeville; and the family farm, Andalusia. Numerous facts about O'Connor and the people closest to her are woven into the site descriptions, as are critical observations about her Catholicism, her acute sense of character and place, and her fierce sense of humor."
I've recently noticed quite a few books that connect authors with geography. In NC, we had Literary Trails of the North Carolina Mountains by Georgann Eubanks, published last year. It's another interesting angle from which to study popular authors (and hopefully a boost to local tourism), and I expect we'll see more in the future. Feel free to share any related books you know of ...