First off, start with a pair of these for $250:
http://www.audioadvisor.com/store/productdetail.asp?sku=ATHASF1.2&product_name=AS-F1.2 Loudspeaker -- Black Ash
Now, add a pair of these for another $120, which brings the total to $370:
http://www.audioadvisor.com/store/productdetail.asp?sku=ATHASB1.2
Now, fill in the center with one of these for $150, which brings the grand total to $530:
http://www.audioadvisor.com/store/productdetail.asp?sku=ATHASC1.2
That's a lot of system for that price. Now, I know this does NOT figure a subwoofer but, for this price you get a pretty robust and musical system that can be the basis for a killer HT/music.
Here's a review on just this combination, albiet the original ".0" version where these are the ".2" version:
http://www.hometheatersound.com/equipment/athena_audition_asf1_asc1_asb1.htm
It'll play quite loud and low like it is, but...
If you really want to blast, you can add a big. bad sub from one of the big sub names (NOT Athena here) and your system will sound like it cost a LOT more than what you paid. You've saved more than enough to give you a healthy start towards saving for that killer subwoofer.