AFAIC, a radial fin design heat sink is as good as it gets for air cooling. I have a tiny (relatively) Thermal Integration (Dr. Thermal) V77L and it keeps my CPU reliably around 40 deg C. But I know of nothing similar for current CPUs. The Zalman CNPS series is nice but pricey and I don't know much about the Thermaltake Orb series. If you're not OCing much, the Tt Golden Orb II might do you - not too overpriced at ~$26.00 shipped from the Egg. I'd skip the heatpipe types as it's just another unnecessary complication.
. Just browse through the Listings at Newegg for your processor type and check out all the radial fin/non-heatpipe types. I'm sure one will work well for you - check the User Reviews on Newegg and the fan-boy reviews around the web (there is a thread about them in the C&C section). Surfacing (lapping) the mating surfaces of the HS and CPU will do more for cooling than a bunch of high-tech frippery.
. I just did a bit of browsing and located this one -
http://www.newegg.com/Product/Product.asp?Item=N82E16835150056 . I've always like Spire/Speeze/Fanner/Masscool (all the same company) for giving you a lot of HSF for low bucks. I could see how the Masscool radials could be improved with a shroud. Easy to make one with some of that heavy aluminum tape that's used on HVAC ductwork, etc.
. Coolermaster has a couple of inexpensive radials that look like they could do the job as well.
.bh.