No, I don't have to "re-lax" I see WAY too many people who want someone else to research their system for them, just so they have to click on the checkout button. That defeats the purpose of buiding your own system. The great thing about building and piecing together your own system is that you are making something that is yours. That's the joy. When you ask for someone to tell you what to buy, you might as well go buy a Dell or Gateway, you would pretty much be getting the same thing.
Anyway, enough of the senile rants.
That setup looks great, but maybe you could find a cheaper 7800gt. if you really need to downgrade something, I would suggest maybe only getting 1gb of the ram and buying the other shortly down the road. Other than that, i can't think of a way to reduce costs while maintaining reasonable performance. Just try to shop around. Get the best prices you can. Also, you probably won't get the best prices by buying from just one retailer.