It is missing the plastic brackets? In that case you'll need to buy an aftermarket cooler that mounts through the board, not one that just clips to the AMD mounts. Some coolers come with hardware to mount to both Intel and AMD boards, but the four mounting holes ARE arranged differently, so make sure the cooler is compatible.
I use and recommend the Xigmatek Gaia over the more often parroted but slightly inferior (and more expensive) Hyper212 EVO:
http://www.techreaction.net/2011/07/07/review-xigmatek-gaia-sd1283/7/
http://www.techreaction.net/2011/11/27/review-cooler-master-hyper-212-plus/4/
Unlike the Hyper212 EVO (ignore the URL; it IS the EVO they tested), the Gaia never throttled, although it wasn't always the coolest depending on the fan used. Both got awards, but if you factor in the price, the Gaia wins hands down. It comes with both AMD and Intel mounting hardware; I'm using this on both an Intel and an AMD system.