Look around. The expensive name brands aren't the only way to go. Shuttle has a some really nice pre-build XPC systems, Ibuypower.com and Cyberpowerinc aren't bad either.
My PC= Hmmm.. wait.. none of those sites touch my PC.. wait! Here! I know one! WAY BETTER THEN ALIENWARE and Cyberinc and iBuy. LMAO, Alienware is totally worthless. My friend has a very new ALX with almost identical stats as my PC except the FX-55, and my 3500+ setup opened a can of 2000+ more on 3Dmark03 whoopass on his "alienware". yeah.. alien technology my ass... more like CRAP....
Now here are PCs that burn up the floor. Pick in your budget. If they are too much, go with iBuy or CyberInc OR I can build you one of your choosing directly of newegg. http://www.hypersonic-pc.com/2001/index.asp
Why don't you simply buy a computer from places like avadirect.com, and then buy a Video Card and a Sound Card seperately, which'll make them cheaper, and those are usually easy to install.
More like 2000-16000 dollar PCs. They are CRAP. Go with CyberPower Inc. They are a good company, I have bought 2 PCs from them several years ago, they run very well. High quality building. This was long before I started building my own!