Well in this area there's Street Toyz Performance, where I used to go, and got most of my stuff from, they're in Rocklin and their number is (916) 660-9882. The guys name is Rich that owns it and hes hella cool.
I've been to Platinum Performance in Rancho Cordova, their number is (916)421-9101. I've been to Redline also out in Rancho, I don't know the number but its out by recycle road, and also Eclipse on Auburn and Greenback in Citrus Heights. Like I know how to get to the places, but I don't know exact addresses. I dunno if one is necessarially better than the other, but if you want directions on how to get to any just ask.
There's a whole lot of shops around, but those are just the ones closest to this area w/o going into Sac that Ive been to.