This is the 12-bar blues pattern that repeats all through the song.
I don't think it's all correct, but it sounds pretty good to me.
The vocal part follows the same pattern, only simpler.
(basically just the bass string and small fill-ins)
This is not to hard to figure out if you listen to the CD
 E                                              (E7) 
|---------------|----9---9------|---------------|----9---9------|
|--------8------|----8---8-8----|--------8------|----8---8-8----|
|------------9--|------------9--|------------9--|------------9--|
|---------------|---------------|---------------|---------------|
|2/7------------|---------------|2/7------------|---------------|
|----0---0---0--|0---0---0---0--|----0---0---0--|0---0---0---0--|
 A                               E 
|--------3---2--|----3-3-----2--|---------------|----9---9------|
|------2---2---5|--2-------2---5|--------8------|----8---8-8----|
|---------------|---------------|------------9--|------------9--|
|---------------|---------------|---------------|---------------|
|7\--0---0---0--|0---0---0---0--|2/7------------|---------------|
|---------------|---------------|----0---0---0--|0---0---0---0--|
 B7              A    | 3  |         E            | 3  |  
|----5-5-7-5----|----3p2-2------|----4-0-----2p0-|0-----0-0-----|
|--4------------|--2----5--5----|--0------------2|------0-0-----|
|---------------|---------------|1---------------|------1-1-----|
|4---4---4---4--|2---2---2---2--|----------------|--------------|
|---------------|---------------|----------------|--0h2---------|
|---------------|---------------|0---0---0---0---|0-------------|