this is the way I think the riff should sound compared to what
the others sounded like(crap)Mine sounds great with distortion.

-------------------------------
-------3p2p0------------------2
------------------------------2
------------------------------2
-----2-----------0----2----4---
---0-----------2----3----5-----
-------------3-----------------

then you would play A,G,C,D,A
                    A,G,C,D,A
                    C,D,A
then                A,A,G,G,CC,DD,A
                    then you would play the riff twice

look at other files to get the lyrics and the chords put together.
there is a more complex riff but this one suites me fine for 
sound and technique.