1. Download canon driver for IP3680 : http://software.canon-europe.com/products/0010648.asp  . Download Linux version in debian format (*.deb)

2. Extract file a file that you have downloaded

3. If you using new version of mint maybe you will get an error when you  install this driver. This error because new version of Mint using Libcups2 but the driver need Libcupsys2 , so you must install the dummy package to deal with this error. Download this dummy package : http://security.debian.org/debian-security/pool/updates/main/c/cups/libcupsys2_1.3.8-1+lenny9_all.deb    ,  install it first and then you can go to install the driver.

4. after you install all driver, go to Printing on menu administration. Clik Add printer. But dont forget to turn On your printer first. And that's it you can using your printer now...