Click the "Finder," select "Applications" and double-click iTunes to open the program.
Click “iTunes” and select “Preferences” from the drop down menu.
Choose the “General” tab in the “Preferences” menu.
Click the “Import Settings” button.
Choose the “MP3 Encoder” from the “Import Settings” menu. This will ensure that your CD is copied to the MP3 format when imported onto your Macintosh computer.
Click “OK” to confirm this change.
Click “OK” to exit preferences.
Insert the CD you want to copy to MP3 into your computer’s CD drive.
Select “Yes” when asked by iTunes to import the CD onto your computer.
Eject the CD from your computer’s CD drive when it is finished importing. (See References 1 and 2)