pricewatch will list the cheapest places to find specific parts from. though if you are looking for the system it is not the best at listing them...

a good thing is that user reviews are included for those sites you havent heard of and might not trust...

it might work out cheaper for shipping purposes if you bought all from the same place, but i doubt that one place will have every part the least expensive.

watch out for OEM or white box parts as they are sometimes lesser quality and/or sometimes not upgradeable (drivers, bios, etc.). a retail box would cost you more, but it may or may not be worth the extra $$$. video card i would buy retail, cdrw/dvdrw drives retail, other than that most things wont matter too much, but retail for the same price is a no brainer...

so you are getting the 64bit processor, are you going to use windows 64bit software or just xp?