Motherboard and memory advice required

[scamartist]

Have bought most of my components already.

Coolermaster CM-690 Dominator case
Corsair HX 620W power supply
Q6600 G0 stepping
8800 GTX OC for a bargain

Need some advice on what motherboard and memory I should go for.
Want to get 4gig of memory so better to get 4 sticks or 2 and would like to overclock processor to about 3 Ghtz.
Any recommendations.

Thanks in advance...