Since it sounds like your media was downloaded from the iTunes Store, you may be able to download it again free of charge:
Thanks for the links Matt, I have managed to resolve the majority of my problems. I have purchased 519 songs from iTunes. All of these songs show "downloaded" in the iTunes store window. When I go to my library most of them are available to play with the exception of about 30. These 30-songs have the "!" to the left of the song name. When attempting to play these songs the message window "The song "xxxx" could not be used because the original file could not be found."
How can I get the iTunes store to allow me to access these songs??
Any assistance will be appreciated.................Ray