iTunes: Delete Duplicate Songs
Posted on Dec 30, 2007 under Software Tips |The easiest way to remove duplicate songs from your iTunes library.
1. In iTunes, click View > Show Duplicates.
2. iTunes will then show all copies of audio files that are duplicates. Choose which copy you would like to delete then right-click on it and select Delete.
3. When you’re done, select View > Show All.
Note: These steps are for iTunes version 7 and above. Visit here if you need steps for older versions.

by Pete, on May 5 2008 @ 5:25 am
So, Show Duplicates does exactly what it says but you now might have to wade through hundreds of dupes hoping to find the right ones to delete! There should be a better filter available to sort the results by age, bit-rate, source folder etc. You had better hope you don’t delete the wrong files.