Thanks to my daughter Autumn, I have discovered a wonderful source of hard-to-find film documentaries about American folk or roots cultures. These films are available streaming on the internet for free. The documentaries were produced by independent filmmakers in a golden age that began in the 1960s and was made possible by the development first of the portable cameras and then by the capacity for synchronized sound. Their films focus on the culture, struggles, and arts of unnoticed Americans from many different regions and communities.
Here is the link: folkstreams.net