Which amplifiers should I buy for my speakers?

dont wast your money on an amp for the front speakers your sterio will handle them just fine. get a 3 channel amp so you got one each for the rear speakers and a sub channel for the sub. and as for what one to choose, search for 3 channel amps with around the 800w mark sub channel and 100w for the speaker channels. when its all in to get the most out of it go to your local car audio shop and ask them to tune it all in so you get the most out of it. doesnt matter what gear you have if it aint setup properly it will sound rubbish when you crank it up.