Hell, fans cost $3, that's nothing. I got a brand new case, all black with a fire red clear plastic front on top of the black (looks nice), has 4 5" bays, 2 3" bays, a side vent intake (most modern chips require this), and a front-panel attachment, fully ATX compatible, all for $30 (not counting S&H).
Don't spend more than $50 on a case is my suggestion. All it has to do is look good and function good, it doesn't have to be made from gem-encrusted gold leaf.