the American South course is now available "on demand", start whenever you like. Just as well, because when I did the course I think Prof Ferris replied to comments on the discussion forum just once. I found the course extremely light. There are nice fragments of interviews/documentaries that the prof. had done with blues singers, storytellers, etc, but the clips are too short. There is a good, longer clip of Pete Seeger talking about the song "We shall overcome"

But if you are interested in American history, I would highly recommend Stephanie McCurry (U of Pa.), The Slave South, on Coursera. It has just finished; you can sign up for the watch list to be advised of the next iteration. In the meantime, "The Age of Jefferson" is available "on demand". Several of the students on the course recommend Eric Foner's trio of courses about the American Civil War and Reconstruction, which are with another MOOC provider, EdX.

there are a couple of songwriting and guitar courses in the mooc ,,, I havent come up with any more re folk music or folk lore.