Is there a program that merges folders together, deleting the same items?

This would be for a Mac.

Okay, I’ve noticed that on my Mac that I have three folders for iTunes music, which is weird. It would take way too long for me to go one by one in each folder, putting them all into one folder and deleting the rest to free up disc space. Is there a program that would do that for me? Or can I just drag all the folders together or something?