Joe,

I am surprised that you were unaware of Hokum. There is a whole slew of this material by various groups of musicians recorded under the name of The Hokum Boys and The Hokum Trio. Such musicians as Tampa Red & Georgia Tom Dorsey (before he took to writing spirituals}, Bob Robinson,Alex Hill, Big Bill Broonzy etc.etc.
Forget Wikipaedia and refer to Dixon & Godrich.

Hoot