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Yes, all you have to do is type mp3 in the search bar of any finder window while the drive you're looking in is selected (highlighted).
 
For MP3s it's easy. From the Finder go to the File menu and select Find...

Select Computer at the top, and for Kind, select Others and MP3 Audio file off the list. Spotlight will take a few seconds but will give you a list of all your MP3s.
 
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