Sharing a Printer from a Mac to AirPrint
http://www.howtogeek.com/102671/how-to-enable-airprint-for-ios-printing-from-any-mac-or-windows-pc/

Thanks to AirPrint Hacktivator you can turn any printer connected to your Mac or Windows PC into an AirPrint compatible printer.  from:
http://osxdaily.com/2010/12/01/make-any-printer-airprint-compatible/