What have you listened to? Are you in my area(BC)?
The Velodyne Deco system is around $500 at A&Bsound, and all you will need is a receiver and speaker wire. It has a 600WRMS, 1200WPEAK subwoofer and good quality sats.
Another option is the Athena Micra 6 system. It has 4 sats, 1 center, and a sub. The subwoofer isn't as good as the velodyne systems, and the sats are a bit lighter, but its a great system for the money. This will also require a receiver.
Both these system have been reviewed by this site. But, with a room your size, I think the velodyne is a better suite because of the more powerful subwoofer.
Any decent Yamaha, Denon, HK, or Pioneer receiver will be able to drive these sets.
SheepStar