HELP with a car SOUND SYSTEM SETUP?

I have a 1992 toyota corolla..and i wanna put in one Pioneer 12" 800w sub with a Pioneer 750w amp, and two 250w Pioneer 6x9's with a Infiniti 200w amp. Would this sound good or should i also put in two more 6" speakers? I am wondering what kind of cables i need to hook all this stuff up...Also, should i build my own box or buy one...