Hi,
I no i've been a long time getting back to you but I have finally sorted out my Limewire, iTunes, iPod problem!. I downloaded the software 'iPod Access' cost me a tenner but was well worth it. Basically I was able to copy all my songs from my ipod back into itunes so I could play them after deleting them from limewire! As you thought it did duplicate the songs on itunes but it was easy enough to delete the ones that I originally had but could not play. I could copy all songs or select certain ones and it tells you what keys to press when you plug your iPod into iTunes to stop it automatically updating and therefore losing songs! Its fab I would recommend iPod Access to anyone. It probably does loads more and there may be a way of doing it without duplicating that someone like yourself would understand but for a technophobe like me it did the trick!!
Thanks so much for your help and advise.