I already am pretty set in stone on the components, i5 2500k, GTX 560Ti, 8g of Ripjaws, 750w PSU, ASRock Extreme3 Gen3 Z68, 212+ Heatsink.
My main question would be, what kind of cases would be recommended? I'm spending most of my budget on the parts, looking to spend <$100 on the case, but don't want something that will look too plain, but I also want something that will have enough real estate fan wise.
As a small, less important question, with those parts in mind, how much wattage in a PSU would be needed to be safe in case of overclock and expansion of RAM.
Ram and overclocking take a minimal extra out of a psu. It is the graphics that is the big variable.
For most users, a GTX560Ti needs 500w with 30a on the 12v rails plus two 6-pin PCI-E power leads.
It is not wrong to overprovision a bit with 650w or so.