Here is my setup, and it didn't cost me an arm and a leg.
I have a Pioneer deck ($180)
Two 6 3/4" Pioneer door speakers (front doors) Built in tweeters ($150)
Two 6 3/4" Sony HD Audio door speakers (back doors) Built in tweeters ($100)
Two 12" Insignia subs (Kit came with 500W amp for $200)
Sony Explod 600W amp (swapped out the insignia) ($250)
Custom made sub box ($50)
Scoche wiring kit and Cap ($100)
Two Pioneer 6x9 speakers in the far back (traded the insignia amp for them)
The whole thing cost me about a grand, sounds really nice and hard to steal (takes three to get box in and out)
If you are not looking for bass then subtract the subs and amps and you will have a pretty good and cheap system.
About the wiring etc, you can get kits at walmart for like 15 bucks. Normally the deck will come with a harness that will work, at least mine did.
Any Jeepers in Edmonton, AB
I am on channel 33.
I live, I ride, I am JEEP.