Thanks for the support guys and/or ladies!
I finally fixed the problem by backing up the phone on iTunes and restoring the whole thing... then restoring the backup. Didn't lose any information, and although it took three hours, the music is now back. And as an added extra, you CAN now delete individual tracks (at least I can!) from the music prog when all your music is on the
cloud. Really strange Apple didn't advertise that, especially because it was one of the big turn-offs with iOS 6.
It took 3 hours, but it was worth it... now if they hadn't gone to iOS 6 in the first place, we wouldn't have this problem... although the wonky maps were entertaining for a while...
Happy repairs, everyone...