iPad 2 is acting up with airprint

[Fonzie91]

I bought myself a Canon PIXMA MX432 printer since the seller at Best Buy said it supported AirPrint. I double checked on the apple support website's browser on AirPrint compatible printers and mine was in the list. I connected the printer to my wireless network and I got it wi-fi printing with my MacBook OS X 10.6.8 perfectly fine. The problem now is, my iPad 2, iPhone 4, and even my iPod touch (latest generation, 4th I believe) won't even detect the printer! I try loading up Notes on all these devices and try to print out a couple of words and it just won't detect my printer!! I tried registering my printer through Canon website, as someone suggested, and it still didn't work. I know this printer is AirPrint compatible because the one on display at Best Buy had stickers across saying it does.
Will I have to pay for a app now? :/