if you don't watercool, I recommend the following:
Athlon 64 3200+ or 3500+ (anything higher is a waste cause these overclock better than the more expensive 130nm parts) - $190 or $250
DFI nForce4 Ultra - $140
2x512MB Crucial Ballistix PC4000 or PC3200 (both are about the same, just whichever is cheaper) - $230
Geforce 6800GT or Radeon X800XL - $375
Maxtor Diamondmax 10 300GB SATA drive, NCQ, 16MB buffer - $190
NEC-5200A Dual Layer DVD-RW - $60
PSU - Vantec VAN-520A, OCZ Modstream 520, Antec NeoPower, whatever 24-pin PSU you prefer - ~$100
Case - Thermaltake Dream Tower - $100
CPU cooler - Zalman CNPS 7700-AlCu - $40
GPU cooler - Zalman VF700-AlCu - $30
Fans - Panaflos are good, apparently, and pretty quiet if you turn them down. The Vantec 120mm Stealth is also quite good and quiet, but all the other Vantec Stealths, even the 92mm ones, can't hardly push any air at all. The 120mm version pumps over twice as much air as the 92mm one, without being any louder.
Anyways, I think that's a good place to start. The 90nm A64s clock better than the other high end chips, hitting around 2.7GHz, versus about 2.5 for the 3800+ and 2.6 for the 4000+, while costing around $400 less. The Crucial Ballistix also overclock great, leaving you plenty of room for OCing your CPU, and even have pretty good timings to boot (2.5-2-2-10 is apparently pretty easy at DDR500 speeds). The 6800GT/X800XL are your best price/performance in the high end segment, so I wouldn't waste your money on an X850XT or 6800 Ultra. The passively cooled GPUs are decent, but may be a bit underpowered for the kinda budget you're looking at (12 pipelines hurts the X800 and 6800). For cooling, the Zalman products provide great cooling while being very quiet. Not silent, but much quieter than even the stock heatsink/fan combos on both the GPU and CPU. And whatever you do, make sure you get an nforce4 mobo and a 24-pin PSU. The PCIe/SATA-II support, and ATX 2.0 compliance, will allow for greater upgrade potential, which is a definite plus for someone spending this kind of cash on a new system.