For compressed air, even camera shops like cathay photo and alan photo do carry them.
Personally I have used them to blow off dust from lens, filters...etc
and General cleaning.
But for CCD, it is not advised, for 2 reasons.
1) The compressed air will discharge liquid when used (it happens when the liquid air is de-pressurised into gas, condensation may take place)
Hence do not point the can at the CCD too close.
2) The strong jet of air (compared to blowers) from the CAN, might "damage" the CCD.
Several camera manuals I have come across have WARNINGs against the use of Compressed air for CCD cleaning.