Here are a few good coolers
Thermalright Ultra extreme 120
Cooler Master V8
Sunbeam CR-CCTF 120 mm Core-Contact Freezer
For the Sunbeam: Sunbeam CR-LGA1366 LGA 1366 retention bracket
I would go with the Sunbeam (the most proven one) , but be ready to have problems with installation. I have seen lots of reviews where people either give up trying to install it , saying it won't fit (it probably does , but they are too impatient) , or they fear breaking something on their motherboard from forcing things. At least now you know where to go in case you have problems , though!!
As far as cases , you should get a full-tower. The 5000 series video cards are huge. Something like this : http://www.newegg.com/Product/Produc...82E16811129043
The 5970 video card is overkill (in my opinion) unless you are going to have 3 monitors running something like Crysis on enthusiast settings. I personally would spend the extra dough on your monitor. Maybe something like this : http://www.newegg.com/Product/Produc...-203-_-Product
I mention this one because it's backlighting is via LED rather than fluorescent bulbs. This saves lots of electricity , is cooler , provides darker blacks , and less backlight bleeding.
Otherwise , you can't go wrong with a Samsung 24"