First Contact
It didn't take too long to figure this out, but i 
believe it's really accurate.
I know there's another tab for some AVA riff somewhere 
on the net but I didn't take the
to read it.

Intro

e|---9--------9--------9--------9--------9--------9----
B|-------10-------10-------10-------10-------10-------1
G|-----6----6---6----6---7----7---7----7---9----9---9--
D|-----------------------------------------------------
A|-----------------------------------------------------
E|-----------------------------------------------------

e|----9--------9------------| 
B|0-------10-------10-------| 
G|--9---7----7---7----7-----| 
D|--------------------------| 
A|--------------------------| 
E|--------------------------| 


There is also another way to do the intro which I find 
e|-----------------------------------------------------
B|---14----------14----------14----------14----------14
G|---------14----------14----------14----------14------
D|------11----11----11----11----12----12----12----12---
A|-----------------------------------------------------
E|-----------------------------------------------------
  easier and sounds a bit more accurate.
e|------------------------------------------------| 
B|----------14----------14----------14------------| 
G|----14----------14----------14----------14------| 
D|-14----14----14----14----12----12----12----12---| 
A|------------------------------------------------| 
E|------------------------------------------------| 


The second part to the riff can start out like this:

e|---------------               e|-----------------| 
B|-----10---10---               B|-----------------| 
G|---6----6------ or like this: G|------14----14---| 
D|---------------               D|---11----11------| 
A|---------------               A|-----------------| 
E|---------------               E|-----------------| 

Of course, I prefer the second way.

The rest of the second part to the riff.
e|-----------------------------------------------| 
B|-----------------------------------------------| 
G|------14----14----10----10----9----9---9---9---| 
D|---11----11----12----12----11---11---9---9-----| 
A|-----------------------------------------------| 
E|-----------------------------------------------| 


Also they hit an A octave as Tom usually tends to use 
e|---------        e|---------------------| 
B|---------        B|---------------------| 
G|--------- and... G|---------------------| 
D|---7-7---        D|---7---7---7-7-7-7---| 
A|---0-0---        A|---0---0---0-0-0-0---| 
E|---5-5---        E|---5---5---5-5-5-5---| 

I cannot wait for this album.