o'hanrahan--Some festivals with folk/camping that I love: Old Songs, Altamont, NY, last weekend in June; Common Ground on the Hill, Westminster, MD, weekend after July 4th (very wonderful, but VERY underattended this past year!)
Also consider "Festivals" that are ALL camping/musicmaking: consider the retreat weekends sponsored by your local folk-music club. The FSSGB in Boston, Pinewoods in New York, FSGW in Washington, DC. You won't find much in the way of commercialism, just people who like to get together and make their own music. Isn't that what folk music is all about?
--Charlie Baum