I've been going to Yakima Folklife for six, maybe seven years. It is a wonderful little festival with a diversified program of musics and arts. The festival is centered around the Yakima Museum on Teiton Dr. But there is an abundance of venues throughout the city. Two pubs near the downdown area, They have me doing a gig at Tim's basement at 11 PM Friday night and at 8 PM at the Garden Stage Sat. These are both new venues for me but I am looking forward to the festival and also will plan on sneeking away Sat,driving about 40 minutes north to Ellensburg to gather with Jen Ellens Catsters.
There is another great festival in Sept at Tri-Cities WA called Tumbleweeds Music Festival. Labor Day Week-end. That is another great time but competes with Bumpershoot in Seattle the same weekend. Almost forgot, I/m not sure where one might camp, you cannot camp or even park at the festival site. You might want to do a campground search for the Yakima area.
Mudjack