Cleaning muck of the sensor is one of those problems that concerns new D30/D60 owners. Canon advise using only air blowers or sending it to them for cleaning. The digicam forums are spattered with reports from owners who've sent their camera to Canon and have it returned even dirtier than it started. I did send my D30 to Canon for cleaning; the sensor did not come back any worse, but it did not come back clean. So now I do it myself, not often, I've done it, perhaps, six times in the 18 months I've had the D30. If you take care, have a clear working area and good lighting, you should have no trouble. Of course, the decision to clean the sensor is yours, don't come whining to me, if you make a mistake. These are the items I have in my cleaning kit:

• Big Blower
  Plenty of photographers say they use those compressed air cans, but I find they spray gunk too easily. There's a clean whoosh for a few moments, and... just before you take your finger of the button... spots all over the lens. The blower is OK for loose particles, but, by and large, I don't find it much help for those sticky bits that cling on to the sensor like SuperGlue.
• SensorSwabs
  These are individually wrapped, sterile bits of cloth on a stick. It's much easier to get at the sensor (actually, the transparent sensor covering) with one of these, but they are expensive. Photographic Solutions
• PecPads
  Lint-fee, ultra-soft wipes that are 99.999% free of contaminants (says the packet). Photographic Solutions
• Eclipse solution
  I don't know why Eclipse is different from other cleaning solutions, but I find it does a much better job with less smearing. Photographic Solutions
• SpeckGrabber
  Another high tech stick, which has a piece of highly adhesive materials that is good for "sticky" particles. Kinetronics Corporation

I've given the US home page for each of these products. In the UK, the Photosol products are available from Crown Digital.

Here are a couple of links to article on how to do the cleaning by people who ought to know:

• Michael Reichmann's method
• Thom Hogan's method
• Copperhill Images method by Nicholas R.