Hi Joe. You might want to take a look at "The Guitar Picker's Fakebook" by D. Brody. It has basically the same repertoire as the popular "Fiddler's Fakebook" - a mix of Celtic and old-time/bluegrass tunes. It is in tab format, and is arranged for flatpicking guitar in standard tuning. However, it is basically single-note melody arrangements, so that might not be just what you're looking for.

Good luck, Marion