Here is my collection of "Race Records". Term for music us negros listened to around the 20s-30s. It's mostly blues here, but there were also a lot of spirituals, jazz, and of course hog-lollow and dirty blues. These blues records are pretty damn rare too, and poorly documented.
Some names are recognizable like Louis Armstrong & Ethel Waters but not so much Peg Leg Howell
Someday I might find a Blind Lemon Jefferson record. Those are really rare.
I could drone on for hours about these things- so ask some questions if you're curious.