Q: Connecting to Canon MP620

When I got my macbook air about a year ago, it automatically detected my Canon MP620 wireless printer.  Now I just tried to print, and it says the the computer is unable to connect to the printer.  I've installed the Canon software disk, and still nothing.  I go to Settings, select Printer, and still can't find my printer.  Any help would be appreciated.  Keep in mind, I'm highly tech-stupid.  M