where should i buy my upgrades

well im a soon to be owner of a 2005 jetta gli 1.8t and i really didnt know where to look to get good advice on buying upgrades such as a new boost chipp to maximize my horsepower, rims and possibly a body kit but i need help from the real vw owners out there didnt want to make any mistakes on my first vw

my favorite is ecstuning.com buy all my shit there...

I dunnp were you live but if its in Mass....i know of a place that specializes in german cars