Ahh, that's a shame. The Tiger Direct store is up here, and you can occasionaly get good deals from them, though since Tax usually ends up to be more than shipping in many cases, I only get smaller parts from them.
I would highly recomend getting a new case then. The newer cases tend to have better aif flow and are fairly easy to use. This of course depends on what case you currently have (I have 2 cases that are Chieftech-esq (A TT Xazer II, and one generic one I got for $30 from the Tiger Store), and they do fairly well airflow wise). I highly recomend cases that use 120 MM fans. I tend to stick with Antec cases, since I think they do a good job, but there are a lot more good cases out there now than there used to be.
And as far as the size goes, the better cooling ones tend to be larger. The Blue Orb II is pretty big, though it's wide, not tall. I'd recomend Tall over Wide, as it will restrict your access to motherboard components less.