GFCEU is a graphical front-end for FCE Ultra written in python. It was previously hosted on my old server. When I didn't renew the domain for the server I had previously used, domain squatters seized the domain. The source code for gfceu can now be found on the fceux sourceforge svn server. FCE Ultra is no longer maintained and has been superceeded by FCEUX (which is essentially FCE Ultra 2.0). However, if you need to use FCE Ultra for whatever reason, you can use the following command to fetch the latest gfceu code from svn:
FCEUX (since 2.1.3) touts a GTK2/GTK3 GUI in the application itself that is enabled by default. However, if you prefer to run fceux without GTK compiled in and prefer to use gfceux for whatever reason, you can fetch gfceux from the fceux svn server as well. Please note that this is no longer maintained, and you should probably just use the GTK GUI within FCEUX.
svn co https://fceultra.svn.sourceforge.net/svnroot/fceultra/gfceu gfceu
svn co https://fceultra.svn.sourceforge.net/svnroot/fceultra/old/gfceux gfceux
I will upload gfceu tarballs to sourceforge when I get around to it, as I see that it is still being packaged in some distributions.