I am not sure what exactly you mean by 'edit', but if you mean allow the GameCube titles to be with titles like Wii Shop Channel, you could use WiiGSC/Crap and create a shortcut channel. Though you would probably need to put the cover file in with the right game id and you would lose about an extra 20 seconds loading the game. But why is this in the tutorials section?
There is but it requires you to manually edit something. Can't remember exactly but try looking for a file called wiitdb.xml. If that's not it then you will have to wait for me to get home from work and check. Not sure if editing that file will cause any other problems though.