You didn't state if you want to go with a new or used amp, or how much power you need for your speakers, or if you have any size/mounting limitations?
www.millionbuy.com usually has tons of deals on amps.
www.crutchfield.com has some decent deals on amps right now if you want great customer service and an Authorized warranty.
If your okay with buying from eBay, this is a great deal on a very good and powerfull amp that's been fully bench tested by an Amp Repair Tech. IIRC, Mike (the seller/tech) will extend the warranty to a year or two for $15 or so...
US Acoustics USB 4085 amplifier:
Good Luck...and welcome to MP3CAR!