Ok, this is on an acoustic and I play it in Drop D(not sure if that's how they do it but it sounds fine either way.

Main riff

e  ------------------------------------------------------------------------
B  ------------------------------------------------------------------------
G  ------------------------------------------------------------------------
D  -------2-------------2------4--------0-------------0-----2--------------
A  ---2-----2---2---2-----2---------0-----0---0---0-----0------------------
D  -2---2-----2---2---2-----2-----0---0-----0---0---0-----0----------------


If you have heard this song you know how slow and tripped out sounding this riff is. And the spacing for the notes isn't right, I did it like that to fit it on one line. Listen to the song for actual timing. Later, I'll do some of the longer, more elaborate stuff by Down. I hope this'll do for now. Later. 

 DOWN

Jail

D tuning

Main riff:

4X 1-3 4th 4X
G----------|-------|-------|-----------------| Keep Repeating
D-------7--|-------|---9-7-|-------5---------| Tune down to D
A---7------|-7---7-|-7-----|---5-------5---5-|
E-5---5----|---5---|-------|-3---3-------3---|


Play this forever.
This is the little harmony part in the middle,
it's clean, right before the arpeggio, listen to it when you play it or
listen on the song.

Remember tune down to D
then
G-----16--------|--12^14-12~~-12^14-12-12^14----|
D--14-----------|----------------------------14-|
A---------------|-------------------------------|
E---------------|-------------------------------|
Repeat numerous repeat
times, not sure
off the top of
my head