So I followed the Migration Assistant instructions that say to go to the System Preferences on both computers, enable "file sharing", and then add the files in question to the Public Folder on the source Mac. But when I go to open the Drop Box on the MacBook, a window pops up to inform me that I can't open the Drop Box because I don't "have permission to see its contents."
I've done everything I can think of to enable sharing, but I'm running out of ideas. (And really need my old iTunes library!) SOS!