ok guys i have a mazda protege5 (wagon)

and i wanted to install a new carputer i built. my problem is this as follows: i have a double din dash and i wanted a screen which will cover the entire 2 dins.(that solved). i have 3 JL 10W7s which will go in the back with their amp.(that solved) what do i use to power my sides? another amp?

ok in regards to power how did you solve the battery drainage problem... i don't want my battery drained... space wont be a problem going to run the entire computer to the back of the car.with just a DVDRW on the front area somehwere... i know alot of extensions!!!
anyhow any advice would be greatly appriciated.