How do I uninstall KDE applications compiled from source?
You can uninstall your programs by typing make uninstall in the folder where you did make install. If you have already deleted that folder, then there is only one way, and it is not good: go to $KDEDIR/bin and start deleting files one by one. If you expect to find yourself in this situation, you might want to consider a program such as GNU stow, found at http://www.gnu.org/software/stow/stow.html.