More food for thought:
Given your suggestion about the Energy brands, you could get a new Energy 7.1 speaker system consisting of two Energy C200 bookshelf speakers as fronts, four Energy C100 bookshelf speakers as satellites, Energy C-C100 center channel and an Energy S12.3 subwoofer. Total for a new 7.1 system is $1430 from Audio Advisor (http://www.audioadvisor.com/).
The energy speakers are the best I have heard at this price point, and the larger C200's with the S12.3 sub would provide enjoyable music listening as well in 2.1 if that is your intent. These are quite common products, and you can probably find these components at a local video store on sale new for less than AA's current prices.
In contrast, the smaller PSB Alpha 7.1 system from AA would cost $1460. Of similar size to the Energy set up but with more capable speakers, the all PSB Image 7.1 system would run $2440 from AA, and an all Epos ELS8 system would run $2600 from the same source.
The Energy system would provide a bigger overall sound and fill a bigger room than the smaller PSB Alpha's, but the Alpha's would be a bit more accurate if that is your bag.
The all PSB Image or Epos ELS8 systems would start to get you at the edge of "performance speaker" territory, but you can see that new those are outside your current budget. The suggestions in my above post will be similarly priced or higher than these two suggestions for a whole 7.1 set up, so used is the ticket if that's your final destination.
Keep in mind what you will be using to drive these speakers. The PSB Image and Epos or any of the other entry level audiophile speakers I suggested above will be less forgiving of source and amplification than the complete speaker kits or the Energy system, so that is another consideration for you.
One last point - I would definitely not scrimp on the subwoofer, as muddy or sloppy bass can really ruin your level of enjoyment. I would budget 30-60% of your total system cost for the sub. It cost a lot of green to go down well.