thetomjefferson :
Thank you. Any other opinions ladies and gents?
It depends on your budget.
I second the 212 Evo recommendation. Everywhere you go you hear people saying how good it is for the price.
I've read that the Noctua NH-U12S is a very good cooler.
http://www.noctua.at/main.php?show=productview&products_id=63
Just so you know, the best air cooler on the market (again, from what I've read) is the Thermalright Silver Arrow SB-E Extreme. Some videos that I've watched have shown that it can perform about as well as the Corsair H100i closed loop water cooler.
http://www.thermalright.com/html/products/cpu_cooler/silverArrow_sb-e_extreme.html
I think it's a little bit cheaper than the H100i, too. It depends if it will fit in your case because it's a dual radiator heat sink.