Go with the one I mentioned, I've never heard of that site and I wouldn't buy parts from different stores. Better off buying it all from one store (PCCG) they're reliable.
And yes it does, a good quality one will deliver good wattage to your components, if you cheap out on a power supply you will have problems and over time you could risk your hardware from blowing up. xD
Seagate Barracuda 1TB's go for about $109 on PCCG, it's not that expensive.
Also try fit a SSD into your budget, it will greatly improve performance of applications you have installed on it. Faster loading times/ boot times all that good stuff.
www.pccasegear.com/index.php?main_page=product_info&cPath=210_902_1006&products_id=17369
Corsair make some decent SSD's and you should be pretty satisfied with the results.
Posted on Thursday, 12th January 2012