You mentioned Airport - do you have an Apple Airport Extreme base station? If so, there's a USB port on it for sharing a printer. AFAIK, though, it won't share to Windows boxes. The Canon model you mention isn't on the compatible list either.
I'm not sure how easy the Linux route would be, but there are probabaly friendly distros out there that will share an inkjet printer as a PostScript unit, but that would involve converting the output, so if you print photos, they may not come out as expected.