Yankee, none of those tunes are hillbilly music. The first is pure Nashville Kuntry, Leo Kottke is crossover, and OZM is country-rock normally, but that tune is jug-band music. Hillbilly music has a banjo, a fiddle, and usually a Mandolin.
...got me there, I don't know shit about country, I really like those songs though. Thanks for the music, Reb,.. great stuff. . .