As long as you have the CD in your posession you can load it on your ipod. When you return the CD it should be removed from your Ipod. If you like it, you should buy it.
You should check with your library but my library has a service where you can download audio books and music from home or at your public library to your ipod/mp3 player. They have a borrowing period after which you should delete them from your systems.
I love it!
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