In a Facebook page for the Old Songs Festival, one person, answering another person's query said that still another person (Joan was his wife's aunt) posted the notice of her death in a Yahoo group that I can't access.

Joan was very active in the capitol city area of New York State, and probably further out than that. If you don't know who she was, news of her death probably won't matter to you, but George may post some more information.

Fox Hollow Festival, Circa 1969-- Joan is the woman with the guitar, center stage behind the mic. (About 16 seconds in)