I'm not gonna go back to the shop, it looked pretty good, had a good range of hardware (it had 3 varieties of 6600GT's on offer), but either way, if he was trying to rip me off or didnt know what he was talking about, I don't want or need his business. I'll go back to the shop that gave me the $850 deal and ask for some better equipment on it and it'll hopefully be around the $1000 mark.
I'll look for the A8V-E Deluxe since I don't need the extra features so much. Maybe the Gigabyte K8NSC, or the Gigabyte GA-K8NF-9 if the A8V-E isn't available. Those three all cost the same, and by the sound of it, none are going to be too noticably bad. They supports the superior (and cheaper) dual channeling. Its 939 so it leaves the door open to simpler upgrades in the future, and should work fine with the AMD 64.
Someone on another board said "first of all, u cant get the gigabyte board as its the nforce3 250gb chipset .'. is AGP not PCI-E." I'm thinking he means the K8NSC? nforce 3 boards are still good for what I want aren't they?
A single 6600GT will be fine for now. SLI isn't needed, and a 6800GT is too expensive, especially when I feel that the 6600GT will be more than powerful enough for my needs. My brother and I combined may play up to 20 hours a week on this thing, neither of us are in it for bragging rights with any friends about who can get the highest FPS or the best settings. I just want it to run reliably and smoothly to be able to enjoy games like Battlefield 2 online.
Thanks for all the help, you lot have been by far the best advice I've gotten. I'm back at uni this week so I won't be able to get a quote on my (hopefully) final set-up until probably the weekend. When I get it I'll chuck it up here.
EDIT: I just read on Tom's Hardware Guide that Gigabyte's nforce3 K8NSC is an AGP board whereas Gigabyte's nforce4 K8NXP is PCI-E. Is this the case for all nforce3 boards when compared with nforce4? I definitely want PCI-E.