You can buy cans of compressed air in some computer stores, or places that have a computer or electronics section. Commonly referred to as canned air, there is no actual air involved. It is a spray can with a long narrow straw to attach to the nozzle, filled with liquefied difluoroethane, trifluoroethane or tetrafluoroethane. The only brand name I recall off-hand is Dust Off.

I've also seen (at Future Shop some time ago and Staples relatively recently) a handle and nozzle designed to take standard size CO2 cartridges. Of course they warn you to only use their brand refills since regular (and cheaper) cartridges could contain trace dust or oil.

A small air compressor (like an electric bike pump, etc) could also work, if it had a nozzle or setting with an appropriate size and speed airflow.