You should check out the Everything Rockabilly thread. Some great options there.

Also, you might like J. Roddy Walston and the Business. Very heavy country and blues influence in what I like to consider an alternative band. I'll post their most well-known song here that you've probably already heard before (it was at the beginning of the movie "Contraband", although I can listen to their entire albums cover to cover)...

I first heard this in one of my husband's video games. The one where ol' buddy goes splat at the beginning.

Allah-Las band