Watch the Inversion Etude: E online guitar lesson by Tommy Emmanuel from Fingerstyle Milestones
There's a lot of songs in E and A, and using these positions you'll be able to get the nice low bass notes, and still be able to play melodies up higher. You need to learn as many good positions as possible. These are all very important in learning this style properly, so I'm going to show you. Here's an E, and now I'm going to A, B, E. So basically the bass part is starting on the low E and then switching to the A I'm just playing that much of the chord and spelling out A, B. Then I switch to the B as a bar chord, starting with the B bass. If you remember what I told you the first note of every bar is the root note of the chord you're in.