If you want to read a fictionalized version of folk songs and the supernatural, Manly Wade Wellman's Silver John series is an interesting read. Supposedly, Wellman didn't make up all of the songs but did make up some, so there is a bit of work sorting between what's real and what's not, but I enjoyed the series a great deal.

(As a side note, Joe Bethancourt recorded an album of songs from the book, which I've been attempting to track down. I bumped the thread recently for unrelated reasons).