No offense but if you need to ask those questions, you may need to have someone help you. Not saying you can't do it, but you should read up alot. But at least your asking questions, thats what we are here for. You WILL need an amp to run subwoofers. Depending on what types of woofers you use, I would tell you to get between 300-800 RMS watts. You can buy customs boxes with bulit in amplifiers from MTX and JL. But you will pay for alot for them. If you want to keep the stock head unit you will need whats called a Line Level Converter. Its taps into either your front or rear speakers and converts them from high level(+,- speaker wire) to low level(RCA). There are a few amplifiers that allow high level input, but there is not a wide selection of them. Then you need to run power, ground, and remote wires to the amp. For a clean install you would probably need to remove your front seats and lift up the carpet to hide all the wires neat and out of the way. Good Luck!