pt,
The best section of Yellow Breeches is the special reg, catch and release area - it's about 40 min north of G-burg at the town of Boiling Springs. There's an excellent fly shop there that can help you out with specifics. For flies I'd have the usual array of terrestrials, mostly small. The trout in this section, although stockies, are heavily pressured and rather hard to hook on surface flies. If the terrestrials don't work, a wet ant dropper with a small nymph works well and will have a better hookup rate. The water is low and clear these days but streamers can always be counted on for some action too. Try white and olive Wooly Buggers. There is a low head dam in the lower special reg section and the still water above it usually has some midging fish too. Good luck.