The Antec 900 case is is of the most popular pc cases with gamers. It is 8.1 inches wide so it can accomodate one of those 160mm tall tower style heatsinks that are popular with gamers. It will be a tight fit but it should be okay.
Here is a link to a recent Tom's Hardware article with useful information about 10 popular cpu heatsinks:http://www.tomshardware.com/reviews/lga-1156-heatsink,2535.html
I know the article states Intel LGA 1156 heatsinks but just about all of them are also compatible with Intel LGA 1366 and LGA 775 cpu's.
Here is a link to a very good web site with more useful information about cpu heatsinks that will help you make an informed decision: http://www.frostytech.com/top5heatsinks.cfm
You can use the Google embedded search feature at the web site to find more information about heatsinks for specific cpu sockets.