SomethingStarWarsRelated said:

What does it mean when music is “tracked”? Because, apparently there was a lot of it in this movie. I know chunks of TPM were used. And I know pieces of the actual soundtrack were not used.

Actually, the meaning that ‘tracking’ references is the practice of using music that is not written exclusively for the film that is being worked on. It can be music from other films, classical or contemporary music that has been released commercially (the film, ‘2001: A Space Odyssey’ is a good example), or even pop music–old and new.

There was a separate release of the AOTC soundtrack CD with one bonus track, "On The Conveyor Belt," that was sold exclusively by the store-chain, Target.