Looking for THe Best Sound money can buy at $100.

I bought the Klipsch Promedia 2.1 system 3 weeks ago on sale for $100(a steal I think since they are $150 at newegg) and I decided to return them because I was not satisfied with the performance of the speakers. The subwoofer was constantly distorting after 30-40% on the bass levels. I'm looking at getting the Z-2300's now(online ratings say the Promedia is a little better). So I was wondering if there is a subwoofer out there that has a built in amp for running external speakers so I could basically build my own system. Thanks.

any1 have any input?