After I bought my 180mm macro and started taking pictures at f32, I realized that I needed to do a better job of cleaning my digital SLRs sensor. I did some research on one of my favorite nature photographers websites: www.naturescapes.net. What follows is a summary what I learned there and my experiences.
The first thing to do was to find out how bad the problem was. To do this i put the camera on the tripod and took a picture of a white wall at f32. After downloading the image and viewing it at 100% resolution the depth of the problem was obvious.

The first thing I did to solve the problem was buy really big blower, the Hama. I considered canned air but read that if you every got any of the propellent on the sensor that you would have big problems getting it back off. The technique I read about involved setting the camera to sensor cleaning mode and holding it with the mount facing down so anything blown loose would fall out, rather than just move around in the camera body. This helped alot, but some stubborn dust remained.

Next I bought some Sensor Swabs and a bottle of Eclipse solution. The swabs are ridiculously prices for such small items. I saved the little plastic spatulas and threw away the pads after I used them. I'm going to try reusing the spatulas with some of the Pec pads that come with the Eclipse solution. I followed the directions that came with the swabs when cleaning. Because I had never cleaned the camera, which is two years old, with a swab before it took two swabs to get it clean.