Welcome to the forums, you don't mention what PSU you have at the moment so I've included one as well.
Abit IP35 (Socket 775) PCI-Express DDR2 Motherboard £69.99
(£82.24) £69.99
(£82.24)
EVGA GeForce 8800 GT 512MB GDDR3 HDTV/Dual DVI (PCI-Express) - Retail (512-P2-E801-AR) £149.99
(£176.24) £149.99
(£176.24)
OCZ 2GB (2 x 1GB) PC2-6400C4 Dual Channel Platinum Revision 2 XTC Series DDR2 (OCZ2P800R22GK) £30.99
(£36.41) £30.99
(£36.41)
Corsair HX 520W ATX2.2 Modular SLI Compliant PSU (CMPSU-520HXUK) £57.99
(£68.14) £57.99
(£68.14)
Seagate Barracuda 7200.10 400GB SATA-II 16MB Cache - OEM (ST3400620AS) £47.99
(£56.39) £47.99
(£56.39)
Intel Core 2 Quad Pro Q6600 "Energy Efficient SLACR 95W Edition" 2.40GHz (1066FSB) - OEM £132.99
(£156.26) £132.99
(£156.26)
Arctic Cooling Freezer 7 Pro CPU Cooler (Socket LGA775) £14.99
(£17.61) £14.99
(£17.61)
Sub Total : £504.93
Shipping cost assumes delivery to UK Mainland with:
City Link Parcel Next Day (Delivered Mon-Fri)
(This can be changed during checkout) Shipping : £8.95
VAT is being charged at 17.5% VAT : £89.93
Total : £603.81