I am dealing with this myself. Had about 20 spots on sensor--some dust, some tiny lubricant spots. Got my Giotto's Rocket Blower today, and it blew about 90% of the stuff off the sensor. I have an Eclipse sensor cleaning kit from Copper Hill on the way, with which I will clean off the oil spots.
If you go to copperhillimages.com you will become an expert on sensor cleaning by reading their information.