Actually there are two guitars in the intro so i've tried to put them together in this 
tab. I play it with an acoustic but i bet it will sound great electric too.

This riff ends when the chorus starts but I think you can play it through most of the 
song as the chords are the same. Listen to the original to get the rytm if you have any troubles.

and by the way... this is my first tab (don't you hate when people write that? :))

e|------3-------3-------3---------------3-------------------------|
B|------------------------------------------------------0---------|
G|------0-------0-------0---------------0---------------4---------|
D|----4-----4-------4-------4---4-----4-----4---4-----4-----4---4-|
A|2-----------2-------2-------2---0-----------0-------------------|
E|------------------------------------------------3-----------3---|

e|------3-------3-------3---------------3-------3-----------------|
B|------------------------------------------------------0---------|
G|------0-------0-------0---------------0-------0-------4---------|
D|----4-----4-------4-------4---4-----4-----4-------4-------4---4-|
A|2-----------2-------2-------2---0-----------0-------------------|
E|----------------------------------------------3-----3-------3---|

Have a nice day and go check out Marianne Faithfulls version of the song. It's pretty 
good but the original is better imo.