where is the fuel filter located at on my car?

my dad bought one for his truck and they had a deal going on (buy one get one half off) so he bought me one....and i hear since your getting cleaner fuel you could improve MPG's

but anyway how hard is it to change and where is it at?

 

I think there's a tech article here or on either Audiworld or AudiDIY.com. It's back by the tank and looks like a semi-pain in the ***.

 

Here's the tech article:

http://www.audiworld.com/tech/eng49.shtml