How to enable AirPrint for any printer from iPad to Mac

My iPad is running iOS 4.21. But the airprint can't find printer on my iPad. It doesn't support my Canon wireless PIXMA printers, like the MX models. AirPrint only works on a few select HP printers. If you are a Mac user, you can use something like Printopia. Printopia is by far the best piece of software that let you enable AirPrint support for any printer connected to your Mac from your iPad.