The thing about buying a home theater sub is that all the engineering is done for you. It doesn't really matter too much in a car because you just want to pound the windows out. All subs (home and car) are made to work best when tuned to a specific frequency. To get that sweet spot, you have to have an enclosure that's built to the specs that hit that sweet spot. Plus, you have to worry about sealing the box, porting it, or both.
Sure you could hook up a car sub to a home stereo, and it might sound ok. But, if you're an audiophile and want to hear all the nuances of the bass, it's best to go with one that's been professionally engineered. It's kinda like riding a dirt bike on the street. Will it work? Sure, but I'd rather ride a CBR.My $0.02

 

yea but he wants to use what he has already not spend more $$$$. every one can buy a powered sub for your home.

yes but did u know u can take a electric motor and use it as a speaker. just hook it up to something and be amazed.

 

I can make a microphone/speaker combo out of two soup cans, two buttons, and a length of string [8D].

 

haha.....

 

Umm, in order to feed the signal into your amp you will need either high level inputs on your amp or rca outputs from your reciever. Might want to check for those.
Another tip, Amps x volts = watts. So, watts / volts = amps or in your case 200/12 = 16.66666 amps is the minimum you will need to correctly run that amp. Which will cost somemoney that you could be spending on a real home speaker. Maybe sell the car stuff for home stuff.