I have an E6750 and I am using an Atric Cooling Freezer 7 Pro, Works beautifully my temperatures are about 30 C idle and 45 C load which is great compared to the stock Intel cooler. This fan has been chugging along for about 3+ years surviving two different CPU's and 3 motherboards and still spins like the day I got it. Is you are sensitive about noise the fan is also absolutely silent.
Here is the link. I have revision 1 which is older and only supports LGA 775, otherwise its the same design.http://www.newegg.com/Product/Product.aspx?Item=N82E16835186134
I highly recommend this cooler.
Note: after market coolers tend to be larger then stock coolers make sure you have the space needed to install them.