Native American Drawings

Artists available here
http://www.derekscottART.com and http://derekart.deviantart.com/

Have you tried your local high school and collage? There are very talented students who would like the idea of making a little money from their talents!
Good luck, give children a chance, you'd be surprised what you can find there.

Google this-I know many tribes have websites for their work and individuals.