The beautifully named Carsten Burmeister writes in with an iTunes problem:
I have too many songs in iTunes! My estimate is that my library holds more than 4 times as many songs as I and my three kids use in our playlists. This is most likely due to us using only about 1/4 of the songs on a CD, but we used to import the whole CD anyway. So now we have thousands of songs we don’t use - and don’t want, but can’t get rid of. It appears that there is no column under View Options that shows if a song is or is not used in a playlist. Thus deleting songs that look unfamiliar is dangerous. So much so that I don’t attempt to clean out my library. Can you help?
There are a couple of ways to approach this one. The easy-but-you-might-kill-some-tunes-you-like method is to select Library in iTunes’ Source list and click on the Last Played heading (if this heading doesn’t exist, Control-click on any heading and select Last Played from the resulting contextual menu to add it). Select any songs that have no last played date attached to them and you’ll be rid of tunes you haven’t listened to (and, hopefully, don’t intend to listen to).
The safer-but-a-bit-more-work method is to open each of your playlists, select everything in them, press Command-I to bring up the Multiple Song Information window, and enter something that will identify songs that you want to keep — a five star rating or “keeper” in the comments field, for example.
Once you’ve tagged all the songs in all your playlists, sort your library by that tag and delete anything in the library that doesn’t bear the tag.