Building a PC

I'm planning on building a computer this summer. Here's a list of items I'm looking at getting. Just doing some preliminary research. This is the first computer I've ever attempted to build, so any tips, criticisms are welcome.

Mobo: ASUS M3A32-MVP Deluxe/WiFi-AP (AM2+ socket) (AMD 790FX chipset)
CPU: AMD phenom QC 9600
Memory: Crucial Ballistix 2GB (2 x 1GB) PC2-6400 800MHz DDR2
Video Card: ATI RADEON HD 2600 Pro 512MB
HDD: Western Digital 500GB SATA
DVD drive: Pioneer 20x Dual Layer DVD Burner DVR-115D
Case: Antec 900 Gaming Case w/ 500 watt power supply (is this enough?)

Also, would I need a network card in addition to the motherboard? (for plugging in ethernet cord)

I'm currently looking for good heatsinks for the processor. I've read some reviews/guides and most say that the one that comes with the processor isn't very good.

I'm also looking for good guides as this is the first time I've ventured to do this.

Anyway, thanks.

 

Heatsink: The one that comes with the processor is good enough unless your overclocking.
Network card: Most Motherboards come with one built in. Check your board's specs.
HDD: Make sure it's SATA2 (Sata300, etc), and your MOBO supports it.
I'd go with a bigger power supply (At least 650).
I'd suggest if your going for an ATI card, get the 3870HD. I prefer NVIDIA right now, but I understand what your doing with the AMD chipsets...so let me know how it works out, because I'm curious.

 

I've been furiously searching and researching the vast depths of the internet, and I've completely reworked what I'm getting. (eventhough this is like 3 months in advance; dangit, i want it now, stupid cash flows)

Any advice, comments welcome as this is my first build

Case:Antec 900 Gaming Case
PSU: PCpower and cooling Silencer 610 EPS12V (concentrated on getting an 80+ certified)
MOBO: GIGABYTE GA-EP35C-DS3R LGA 775 Intel P35 (4 DDR2 slots, 2 DDR3 slots for later upgrades)
CPU: Intel Core 2 Quad Q6600 Kentsfield 2.4GHz (I've always bought AMD products but they seem to be going down :/ )
Memory: Patriot Extreme Performance 4GB(4 x 1GB) 240-Pin DDR2 SDRAM DDR2 800
Vid Card: MSI NX8600GT-T2D512E OC GeForce 8600GT 512MB 128-bit GDDR3 (I don't do any hardcore gaming so I don't need the top end stuff)
HDD: Update Western Digital Caviar RE WD2500YS 250GB 7200 RPM SATA 3.0Gb/s

Also have sound card and speaker setup both from Creative. Going to run Vista 64-bit Home Premium (not sure if ultimate is worth it). already have keyboard/mouse/LCD display picked out.

thanks