Ok, there are two viable options. Patience, or compromise.
Patience (until Q4 2011) will allow you to get one of the socket 2011 intel sandy bridge enthusiast processors. Quad channel memory, massive amounts of input (pci-e and sata), and a price that will likely be crazy.
Compromise leads to either a socket 1366 or a socket 1155. The former leads to an older processor which has limited upgrade potential, and the latter is limited to 16 GB ram.
1366:
http://www.newegg.com/Product/Product.aspx?Item=N82E16813128423&cm_re=1366_motherboard-_-13-128-423-_-Product
http://www.newegg.com/Product/Product.aspx?Item=N82E16819115224
http://www.newegg.com/Product/Product.aspx?Item=N82E16820220542
http://www.newegg.com/Product/Product.aspx?Item=N82E16814131393
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139016
http://www.newegg.com/Product/Product.aspx?Item=N82E16835106150&cm_re=cpu_cooler-_-35-106-150-_-Product
http://www.newegg.com/Product/Product.aspx?Item=N82E16822145473
$1438.92 - remaining funds for sata cables, thermal paste, and fans. No consideration for case, OS, or expansion beyond video card. Potentially unlockable 6950 (6950->6970), potential for crossfire, and plenty of processing horsepower for the budget.
1155:
http://www.newegg.com/Product/Product.aspx?Item=N82E16819115070
http://www.newegg.com/Product/Product.aspx?Item=N82E16813128480
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231442
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139016
http://www.newegg.com/Product/Product.aspx?Item=N82E16814127562
http://www.newegg.com/Product/Product.aspx?Item=N82E16835118003
http://www.newegg.com/Product/Product.aspx?Item=N82E16822145473
$1462.93 - remaining funds for sata cables, thermal paste, and fans. No consideration for case, OS, or expansion beyond video card. Potentially unlockable 6950 (6950->6970), potential for crossfire, and plenty of processing horsepower for the budget. I went slightly crazier on the processor and video card to compensate for less ram and less other expansion options.
*There are copious rebates on most of these components. I haven't included them because they aren't reasonable if it takes 10 weeks to process them, and the credit card company won't accept a rebate in process as payment.
In your position, I would wait 4 months. Bulldozer is coming soon, 2011 socket debuts at the end of this month at Computex, and I don't see lack of Japanese components as a good thing for costs relating to demand. A little patience may let you get these components much cheaper, or get better components for the same price.
If I had to buy, I'd go 1366. It gets beaten in gaming performance, but the extra ram and extra cores are excellent for heavy processing. Additionally, the recommended video cards could be traded out for twin 6870s; lower price but very similar performance is crossfire.