Many ITX cases these days have full size ATX power supplies wedged in there somewhere. Some will have SFX or SFX-L powersupplies. I have seen only a handful of mATX or ATX cases that use these though.
Your case, is a standard ATX. Unfortunately, the manufacturer does not list the maximum length, so don't go too craxy on a huge PSU. Given the price of that case, I doubt you'll be dropping $200+ on a massive powersupply, but just something to keep in mind while you're shopping for your PSU.
PS. EVGA's gold 550W is a great PSU and is very reasonably priced.