This song has only got two riffs and is played on an acoustic guitar.
I'll put the bass tabs here also..lol
Oh, my first tab btw. :P

Main riff:
e|-----------|
B|-----------|
G|-----------|
D|-------5~--|
A|-----5-----|
E|-3-3--(3)~-|

Every once in a while you'll hear an other riff

Main riff + other riff:
e|------------------|
B|------------------|
G|---------/4-------|
D|-------5---5-7-5~-|
A|-----5------------|
E|-3-3--(3)---------|

That's pretty much the whole song.
The second riff might have some extra notes but this is pretty much the basis the make 
sound good.

Bass tab:
G|---------|
D|---------|
A|---------|
E|-3-3---3-|

Have fun with it.