Here are some 1915-1940 Black teams:

Okmulgee (Okla.) Merchants, San Antonio Black Broncos, Monroe (La.) Monarchs,Little Rock Black Travelers (independ.), New Orleans Black Creoles,New Orleans Stars, San Angelo Colored Sheepherders,Claybrook (Ark.) Tigers,Houston Black Buffaloes, San Antonio Aces, Austin Black Senators.

Also see: http://www.austinchronicle.com/issues/dispatch/2003-07-04/xtra_feature.html

And: http://www.pitchblackbaseball.com/nlotmwilliamhaygood.html

Some of the larger city teams played in the Tex-Olka-Ark. League. I hope this helps.