12 Bar Blues by Jody Worrell is a free video guitar lesson teaching one of the basic fundamentals of blues. You'll learn how to play a 12 Bar Blues chord progression in the key of E. We'll first cover the chords that make up this progression (E7, A7, B7). Next, you'll learn the order and length to play each of the chords. To get further into blues rhythm guitar, check out Jody's Blues 101 - Rhythm premium lesson.
12 Bar Blues Chords (printable tab)

Here is our 12 Bar Blues Progression in E

Blues 101 - Rhythm by Jody Worrell is a downloadable Quicktime video lesson that will teach you the basic concepts of playing rhythm for blues guitar. Jody will teach you nine different blues chords and two different strum patterns with a bluesy feel. We'll play these new chords and patterns with a jam track to help you practice your timing. Included in the downoad is a .pdf with chords charts.