The file you download from the internet will likely be in a .zip format, so the first thing youll have to do is decompress it. If you want to decompress it from the terminal, use the unzip command.

Once you've downloaded the .zip file containing the Raspbian image, you'll naturally want to unzip it. Fire up a terminal on your Linux box and cd to your home directory via the "cd ~" command.

Unzip the 2012-10-28-wheezy-raspian.img file you downloaded before, and point the Image File browser to its location.