If you can get a hold of a CPU Magazine July 2002 issue, they have an interesting review of various speakers. The highest rating of all - including the 2.1, 4.1 and 5.1 was the Logitech Z-560, which the claim is equal in quality to Klipsch 4.1 for a lot less price.
I know in Canada right now, at Staples, they are $249.00cad, which is about $160.00usd I believe. They also offer a mail-in rebate of 75.00, which brings the price down a lot. The speakers are also THX certified, a technology I am aware of, but not very familiar with, but apparently real good, depending of course upon whether your sound card also supports THX.
Anyway, hope this helps, sounds like you are kind of looking for the same thing that I am at the moment, and I'll probably get me a set tomorrow.
Cheers,
Hagen