Chord/Tab song: By the Sword

Not sure if its the right key or not, done by ear, it's close enough for me.
( Tab from: http://www.guitartabs.cc/tabs/s/slash/by_the_sword_tab.html )
Main riff
[1/2]

E|--------------------------------|
B|--------------------------------|
G|--------------------------------|
D|-------3b-----------------------|
A|-0h3h4---5-4p3p0-3-5------------|
E|--------------------------------|

A variation
[1/2]

E|--------------------------------|
B|--------------------------------|
G|--------------------------------|
D|-------3b-----------------------|
A|-0h3h4---5-4p3p0-2-1------------|
E|--------------------------------|

Another variation
[1/2]

E|--------------------------------|
B|--------------------------------|
G|--------------------------------|
D|-------5b-----------------------|
A|-0h3h4---5-4p3p0-3-5------------|
E|--------------------------------|

this is all i've figured out, hope its good, and if not, hope it gives you a basis
on which to figure it out yourself on.
Thanks.