I'd go with newegg or tigerdirect, I've ordered from those two places before and have had no problems, and the prices were comparable to anything.
as for the cases and your cooling concerns, just look for a case that has provisions for maybe 2 80mm fans in the rear or 1 120mm would be even better since it flows more air at lower speeds which makes it quieter, same for the front. Antec, Coolermaster, Thermaltake, Aspire, Lian Li, there are a lot that are good. If you look on newegg they have user reviews of the products, read those and it'll give you some idea of what it's like.
When all else fails...Ham Radio!
I still have the same old HP DV9700T laptop I've had for years...still kickin'