To Hear Your Banjo Play is a documentary by Alan Lomax from 1947. It is narrated by Pete Seeger and features Woody Guthrie, Sonny Terry, and Brownie McGhee among others.
Wade Mainer played a two-finger style of banjo, between old timey and bluegrass. Here is an interview he did with David Holt at the age of 97. Part 2. Part 3. Still playing strong!
June Carter and Johnny Cash appear on Pete Seeger's Rainbow Quest. June reminisces about the Carter family and A.P. Carter. They all sing It Takes a Worried Man. Johnny sings As Long as the Grass Shall Grow. Finally, June sings I Am Thinking Tonight of My Blue Eyes.
Tom Dula was a real person. Who knew? The Kingston Trio's version of Tom Dooley is the most famous. It says here that Doc Watson's great-grandparents were the Dooley's neighbors. They say Ann Melton confessed before she died... "Folk music is serious business."