How can I shorten a piece of music in my iTunes library?
If you want to get rid of a long fade in&out or a long silence you can use the information window (cmd+i). Switch to the Option tab and set the start and stop time.
If you want to permanently remove parts at the beginning or end my personal tip is to open it in QuickTime X and use the Edit > Trimm function (cmd+T). All you have to do is move the yellow sliders at the left and right-hand side.
If you want to cut parts out somewhere (random) within the music I also suggest Audacity.
Thanks Mike, I didn't know you can set start and stop times. That's cool
No problem ~ FYI those start and stop times also take effect on your iDevice if this is a concern for you. It's a nice option without having to re-encode and sacrifice music quality.
Do you mean cut bits out of it?
Try http://audacity.sourceforge.net to edit your music.
You can find tutorials here: http://audacity.sourceforge.net/help/documentation