DEbian Font MAnager a.k.a. dfontmgr (available through the Synaptic Package Manager) is helpful when you want to register and unregister fonts on a Debian / Ubuntu system.

After installation you can start the manager, which is a GUI for the Defoma package, from the command line. Type sudo dfontmgr (you need to be root to make changes to fonts). It does not look very pretty but installing and uninstalling fonts should now be easy.