A question about hardware amplification.

DISCLAIMER: I know very little about electronics. There will be at least one (but no greater than 5) statement(s) or question(s) in this post that will be born out of complete ignorance. Thank you for your patience.

A few months ago, my friend and I hacked a CRT television to act like an oscilloscope-esque music visualizer (video here). It was a great deal of fun, and I'm working on another one with more functionality to it, and Max/MSP will be involved.

The first one was hooked up to my friend's home stereo for amplification (can't remember wattage, but it was turned down to about 25%). In the second TV, I'd like to have some sort of integrated system, like a circuit board that I can attach to the inside of the case of the TV. It'd be even better if I could somehow leech from the power going into the TV. That way, I could have one plug into the back of the TV that I could feed any audio into and not have to worry about the amplification.

It'd have to be a stereo amplifier, with independent amplification settings. The idea is that running a pure saw wave into each channel (at the appropriate rate) would draw a line from one corner to the opposite.

Now, the idea here is that I could use 2 outputs from my firewire interface to control the visualizations independently from the music. I'd also be able to use jitter to some extent to control... something, I don't know without trying it first.

Is there any cheap/compact alternative to a home stereo amplifier that I could use to amplify my audio signals, or am I just going to suck it up and accept that electronics aren't magical?