Step1
Start with your motherboard and CPU combination for your gaming PC. You can't go wrong with anything Intel. Buy the most powerful CPU you can afford.
Step2
Go with anything Kingston for RAM. Know that you have to have room to grow for your gaming PC. Buy as much RAM as you can fit and afford.
Step3
Scrimping on a video card is a mistake. Consider products made by Asus.
Step4
Consider enhancing the sound. One option is a sound card by Creative, like a X-Fi XtremeGamer or X-Fi Gamer Fatal1ty.
Step5
Get a screaming hard drive, like Raptor's SATA 10,000RPM 150 GB. You can get a second hard drive if you want.
Step6
Refrain from adding a floppy drive. However, a good CD/DVD drive is a priority. Asus makes a good one. You could add a second CD/DVD drive.
Step7
Install an external drive--a must for any gaming PC these days. You can go from ones that are 80GB to 500GB. You will have plenty of storage for any contingency.
Step8
Make sure you have a good case to hold all your goodies. Antec offers one with a high performance liquid cooling package. Add a Seasonic 700W (modular) power supply, Swiftec Apogee Waterblock (3/8 inch) tubing and a Danger Den cooler for 8800GTX/Ultra with 3/8 inch tubing, and you are good to go.
Step9
You must have cool accessories when outfitting your gaming PC. A nice Bluetooth USB adaptor, a wireless USB adaptor, an USR 56k external USB fax adapter, at least two network cards, a remote control for your OS, a nice card reader by ATech, an ATI TV Wonder 650 PCI TV Tuner and a second TV tuner are options to consider for your PC.
Step10
Get a good monitor. Going cheap here would not be a good idea.
Step11
Help your sound with good speakers. Ones by Bosch, Logitech or Cambridge Soundworks are nice. Just make sure they have anything from 2.1 to 5.1 channels with 30 to 70 watts.
Step12
Top your gaming PC off with a nice wireless mouse and keyboard, XP or Vista Ultimate, some thorough virus protection software (Panda, Norton, what have you) and an Office program that includes Word.