I have bought and RMA'd stuff from Directron. They're a perfectly good internet retailer.
I also really like Provantage. They tend to be a little cheaper on Printer supplies and some network kit than other places online.
Anyway, yeah... overclocking C2Ds. Really, really easy. Been saying so for a while. I get better results from E4300s than E6320s, due to the higher multiplier. I've tried lots of expensive air-cooling stuff, too.
I didn't like the Scythe Ninja/Infinity cooler. My system overheated constantly under them.
My system does better with a Geminus II cooler (overall temps are much, much lower than with the Scythe), but it's so completely enormous that it's actually painful to try to work with it. I have a Geminus II on my gaming system right now.
I have a similar Silverstone Nitrogen cooler on the system next to my bed, which manages to get temps about 5C cooler than the stock Intel fan, when combined with a non-sucky fan (Noctua, Scythe or Antec 800rpm).
My current favorite is the Thermaltake V1. Seems to cool better than a Scythe, and it's vastly easier to install. Basically, it's less work to deal with. I like that.
Also, there's nothing wrong with Intel's stock cooler, but it's a little bit loud at times and I don't like that there's no fan guard on the stupid thing.