Adding an amp and sub?

I want to and a sub and a amp to my stock head unit (99 Accord EX) 1: are there pre outs on this head unit 2: where on the web can I find schematics 3: any suggestions on a setup my current setup consists of stock fronts and sony xplod 3way 6x9 rear. This is weak the fronts carry all my bass and over power the rears

Thx Mullen........