Removing leftover application icons in Linux
This worked for me using Gnome 3.6 but should hold true for all the other Linux Desktops that are out there.
find . -name *.desktop
Alternatively you can also filter what you’re looking for
find . -name *.desktop | grep ApplicationName
Then simply remove the .desktop file that you find and the icon should be gone! I had to do this a few times after some leftover Wine programs I found Linux alternatives to.