cdgtools v0.2 now includes a GUI version of the CD+G ripper, from which you can edit your track names and encode the tracks to MP3+G. This version also includes built-in FreeDB/CDDB support so you no longer need to download cddb-py to get track names from FreeDB.
Release v0.2 can be downloaded from here:
cdgtools is a software suite for handling CD+G disks and MP3+G files. It can be used to rip CD+G karaoke disks and encode to MP3+G files. It is the first and only CD+G ripper available for Linux systems.