Offhand, I can recommend the Chuck Guillery, Earl Hooker, Elder Roma Wilson, Sonny Simmons: Live in Paris, and the I Have To Paint My Face collection.
Knowing Chris Strachwicz' (the owner of Arhoolie Records) releases in other genres, I'm sure that there are a lot of Mexican and Tex-Mex recordings on that list that are worth hearing, but I'm not familiar enough with that music to recommend anything.