As far as I can tell, this is in standard tuning and is derived from a simple 12-bar blues, reading as follows:
E	E	E	E
A	A	E	E
B	A	E	E
I don't care if that's how a twelve bar blues song is normally played; that's how THIS one is played.

Here's that same thing w/ the actual notes played:

      BAR 1	(E)   	    BAR 2	(E)
E|------------------------|-----------------------|
B|-------5--3--5----------|-------5--3--5---------|
G|-------4--2--4------2---|-------4--2--4------2--|
D|--------------------2---|--------------------2--|
A|--2---------------------|--2--------------------|
E|--0---------------------|--0--------------------|

     BAR 3	(E)              BAR 4	(E)
E|------------------------|-----------------------|
B|-------5--3--5----------|-------5--3--5---------|
G|-------4--2--4------2---|-------4--2--4------2--|
D|--------------------2---|--------------------2--|
A|--2---------------------|--2--------------------|
E|--0---------------------|--0--------------------|

    BAR 5	(A)              BAR 6 (A)
E|-----------------------|------------------------|
B|---2---0-2-0-2-0-2-0---|---2---0-2-0-2-0-2-0----|
G|---2---0-2-0-2-0-2-0---|---2---0-2-0-2-0-2-0--0-|
D|---2---0-2-0-2-0-2-0---|---2---0-2-0-2-0-2-0--0-|
A|---0-------------------|---0--------------------|
E|-----------------------|------------------------|

    BAR 7	(E)              BAR 8	(E)
E|------------------------|-----------------------|
B|-------5--3--5----------|-------5--3--5---------|
G|-------4--2--4------2---|-------4--2--4------2--|
D|--------------------2---|--------------------2--|
A|--2---------------------|--2--------------------|
E|--0---------------------|--0--------------------|

    BAR 9 (B)                BAR 10 (A)
E|------------------------|-------------------------|
B|------------------------|-------------------------|
G|---4--4--4--4--4--4--4--|---2--0--2--0--2--0------|
D|---4--4--4--4--4--4--4--|---2--0--2--0--2--0---2--|
A|---2--2--0--2--0--2--0--|---0--0--0--0--0--0---2--|
E|------------------------|-------------------------|

    BAR 11 (E)	  BAR 12 (E)
E|------------------------|-----------------------|
B|-------5--3--5----------|-------5--3--5---------|
G|-------4--2--4------2---|-------4--2--4------2--|
D|--------------------2---|--------------------2--|
A|--2---------------------|--2--------------------|
E|--0---------------------|--0--------------------|

For the most part, that's the verses.  For the most part.  Since this is a blues song, there's a lot of improv, especially as the song progresses.  Like I said, I don't have the time or energy to tab it all out.  If you do, be my guest.

The second and fourth verses have a different E riff for the first 4 bars:
E|------0-----0-----0-----0-0-0-------|
B|----0-----0-----0-------0-0-0-------|
G|--4-----3-----2-----0h1-------------|
D|------------------------------------|
A|--------------------------------2---|
E|--------------------------------0---|
And then the other 8 bars are the same.

Now there's also a part w/o lyrics that is just heavy power chords and a lead. We'll call it the "chorus".  To lead into it, play A5 at the end of the 12th bar.
CHORDS:
E5	E5	E5	E5
A5	A5	E5	E5
B5	A5	E5	E5
Listen to the song for the rhythm.  Also I don't plan on tabbing out the lead parts, but they're most likely in the E pentatonic (12-14-15), with some thrown in on the top of the A (17-19-20).
To end the chorus, play:
A-------------------------------
E---4--4--5--5--6--6--7---0--0--
...and then back into the verses.

The outro is the standard E riff.  End with a E5.
Also, the intro is the standard E riff played 8 times before the lyrics come in (2 w/o drums, 6 with).