Although you are unlikely to find genealogical information at Smithsonian Folkways, I have often thought that audio recordings are one of the most direct ways of experiencing the past and getting under the skin of people long gone. Moses Asch had great vision. Try the podcasts here: Sounds to Grow On is a good place to start and this episode on Work Songs a great example of what I mean, as is the one on children's songs.
I've been spending hours listening to the likes of Woody Guthrie and Paul Robeson - both truly remarkable individuals. Don't miss Woody Guthrie's Talking Hard Work song.
Also, under the Folkways collection don't miss episodes 13-15 'winds of change', including the labour, civil rights and women's movements.
If that isn't enough, try a search on your area of interest, for example on Rhodesia we have this list. You can preview recordings by following links to individual albums.