In what you could get with two video cards you can save money and buy one. I think the 4350 HD Card is what everyone is drooling over these days, If you don't 'want' ATi you can try the 9800 GT or the 2** Nvidia cards. Building a monster PC will need a lot more than a quad core processor and a huge wattage supply. I'd slim out a few hundred watts to be safe, say, 700?(I know I shouldn't talk, but the rosewill 950w was on sale).
What are you looking as far as ram?
You seem to have enough cooling as far as your case goes, what about your hard drives? Raid configuration?
I will be the first to tell you, the triple sli setup is a waste of time. Scratch that - MONEY.
The stock fan supplied with your quad core will keep it as cool as it needs to be. Do you want to overclock your processor? Then look into another cooler with a copper bottom i believe(stay away from ceramic, i believe steel or aluminum is a good one too).
The CPU cooler, I wouldn't know, start out by looking for the CPU chipset, read the reviews and compare with which one is the easiest to setup and the best temperatures.