Okay then ... Nice budget!
First up we'll start with the power supply! As you may wish to put in multiple GPU cards I then recommend a Seasonic modular power supply of at least 850 watts! The Seasonic would be the X series 850 watt
http://ncix.com/products/?sku=58217&vpn=X-850%20Gold&manufacture=Seasonic%20Electronics $212.34
Next the CPU! I'm recommending the i7 2600K for you as I guess 3D rendering will need the most herbs under the bonnet!
http://ncix.com/products/?sku=57960&vpn=BX80623I72600K&manufacture=Intel $336.93
Now the motherboard I'm guessing go all out on a GIGABYTE or ASUS motheboard! For this build I'd suggest the ASUS Maximus IV extreme for the best SLI/Crossfire support! This will mean that a large case such as the HAF X is needed to fit it though
http://ncix.com/products/?sku=59315&vpn=MAXIMUS%20IV%20EXTREME%20REV%203%2E0&manufacture=ASUS @ $354.36
GPU I'd recommend 2 ASUS GTX 460 or 1 ASUS RADEON 6950 with the possibility of upgrading to 2! I'll leave this one open however because I'll depend on which GPU platform your 3D software benefits most from! If CUDA is preferred then the NVidia is the way to go (GTX460), if both CUDA and AMD STREAM are supported then I'd recommend the AMD RADEON 6950 as it is the newer card and offers better performance (plus more memory for that massive monitor setup!) NVIDIA OPTION:
http://ncix.com/products/index.php?sku=54506
$177.51 * 2
AMD option:
http://ncix.com/products/?sku=59248&vpn=EAH6950%2F2DI2S%2F2GD5&manufacture=ASUS $318.88
HDD just get a Western Digital Blue 1 TB for files and an SSD for the OS! SSD vertex 2 $369.99
http://ncix.com/products/?sku=53310&vpn=OCZSSD2-2VTXE240G&manufacture=OCZ%20Technology&promoid=1320 HDD
HDD http://ncix.com/products/?sku=56022&vpn=WD1501FASS&manufacture=Western%20Digital%20WD
Case needs an EATX for the motherboard
http://ncix.com/products/?sku=41137&vpn=PC-A70F&manufacture=LIAN-LI @ $184.98
RAM some low latency GSKILL would do fine
http://ncix.com/products/?sku=58100&vpn=F3-12800CL7D-8GBXH&manufacture=G%2ESkill @ $140.23
DVD Sony Optiarc $29.98 --
http://ncix.com/products/?sku=54136&vpn=AD-7260S-0B&manufacture=Sony%20Accessories
Cooler maybe this -- $64.99
http://ncix.com/products/?sku=53612&vpn=CAFA70&manufacture=Corsair\
Which is 2110 aprox for the AMD radeon GPU ...
Hope this helps and I'd be happy to help refine this build once I learn a bit more about the hardware requirements of the 3D rendering software!
Cheers,
Luke