| I'm a big fan of Jack's music, and I've played along with some tunes while listening, but I don't remember any specific basslines. Reason?
Because they're mostly I-IV-V progressions. I remember he used G, A, and D major a lot. I'll listen to some songs, and figure out the chord progressions and keys, and post those for you. The rest is up to you. | 
Jack Johnson 
