Well I see all the posts are here, so I'll just post my Idea of my 1.5k-under build here:

Antec 900 Case (Note: I have already bought the case so the stuff has to fit } $100

Intel Core 2 Quad Q6600 Kentsfield 2.4GHz LGA 775 Quad-Core Processor Model BX80562Q6600 - Retail $200
EVGA 132-CK-NF78-A1 LGA 775 NVIDIA nForce 780i SLI ATX Intel Motherboard - Retail $250
***Western Digital Caviar SE16 WD6400AAKS 640GB 7200 RPM SATA 3.0Gb/s Hard Drive - OEM 90$
***ZALMAN ZM850-HP Continuous 850W ATX12V V2.2 / EPS12V V2.91 Modular Heatpipe-Cooled SLI Power Supply - Retail 180$
XFX GX260NADF9 GeForce GTX 260 896MB 448-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card - Retail $300
LITE-ON 20X DVD±R DVD Burner Black SATA Model iHAS120-04 - OEM $25
***G.SKILL 8GB (4 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Quad Kit Desktop Memory Model F2-6400CL5Q-8GBPQ - Retail 180$

Note: These are all off of Newegg.com, that doesn't mean I will be buying from them, I may look for other places like TD and Buy.com.

I'm not worried about enough power, but will I have enough space? I plan on getting 8 gigs of ram later on, another HDD and 3-way SLI. I will not be overclocking anything either. The 260 GTX seems to be a better buy, should I make the upgrade to the XXX edition for the GTX 260? Or is the 9800 GTX a better buy, this is my first build, I'm a bit nervous, So please help me !
And I probably need to get a 64-bit OS, but which should I get?
EDITED*

Well if you really plan on upgrading to 8GB's of ram anytime soon, (I wouldnt) then you might as well go with a 64 bit OS now. It will run just fine with 2 gb or ram while you wait to upgrade. Do you really need 1200 watts? Even with 3 way SLI, I think it would be overkill. Check this out:
http://www.newegg.com/Product/Prod [...] 6817379007

hd 4870 is best buy

You can't 3 way the 4870's though if you wait till the 4870x2 comes out, you can get 2 of those for your pc to make one great visual experience. (hope you have a large monitor)
Also, don't cheap out on the HDD. http://www.newegg.com/Product/Prod [...] 6822136218 9 bucks more, 640gb.

Yes you can cant you?

@ Suicide,
To be honest, I'm not very good with PS's and I don't know voltages very well. So would something like 850 watts would power 3 way cards? I will check into the PS you recommened me, I think you saved me 150 dollars XD, now I can buy the 8 Gigs of ram and just go 64 bit XD. Thank you

@Pulasky,
I've never used an ATI GFC, I'm not familar with them at all, but I check the Specs on a 4870 and I noticed these differences: the 4870 has 800 Stream Proc., I guess the more is better, but thats twice as much as a 260GTx, WOW XD. The 260 GTx has a better memory clock going about 2.0Ghz. I could 3 way crossfire it looks like, but what are some of the other things that I might not see Whats holding me back from ATI is, well I've never used them and I'm a bit scared I guess XD.

@Mark,
Thanks, ill get the better HDD XD, I didn't really pay attention to those

I think the 4580 does support 3 way... it has two crossfire connectors >.>" Or the Sapphire one does that I'm looking at

BTW would everything fit inside the case ok?

Yea man 850 watts of quality power would serve you just fine. And I also agree that 3 4870's would be a better buy. Even just 2 would be a monster

http://www.extremetech.com/article [...] 590,00.asp
I stand corrected. You CAN use 3 in CF.

^ There we go, although (not trying to be an ass) I think the "proper" term when using more then ATI 2 GPU's in a multicard configuration is Crossfire X.

Hehe yea.

X is correct

Wait, can it Quad CF....X XD
Reading the article has me a bit confused, which ones can quad?

You can quad any ATI card in the 38xx series or above.

Well that article says up to four can be used in Crossfire X. Like I said the new 4870x2 to be released soon can be used in quad easily.

I do believe that you can use more than 2 cards in crossfire, but I thought I read that there is minimal (if any) support for more than 2 - that was the argument against having 2 4870x2. Maybe they'll support it better soon, but I believe I had read that the extra cards didn't do a ton extra.

I read an article about the single 4870 Radeon from ATI, no crossfire. They seem to perform just as well as 260s except a few dollars cheaper.

I think either buy two/three 4870s or I'll wait to buy the 4870x2 or wait for the price drop on the Nvidia Cards. The Nvidia seem to have better AA, while it looks like ATI was having trouble with AA and no-AA (Anti Aliasing)

Seems like the Quad CF-X isn't very efficent. 3-Way or 2-way seem the way to go for ATI. I'll sleep on it and update my build tommorrow.

ATI fixed their AA problems with the 48xx series, btw what resolution will you be playing at?