Launch your web browser and navigate to itunes, if you don't already have iTunes on your computer. Download the iTunes media player, selecting either "iTunes for Mac" or "iTunes for Windows." Enter your email address, then click the "Download Now" button. Wait for the file to finish downloading, then click the "Open File" button. Follow the installation instructions provided by the application.
Open iTunes and change the import encoder to MP3. Click "File," then choose "Preferences." Select the "General" tab, then choose "Import Settings." Click the drop-down menu and select "MP3 Encoder." Click "OK."
Insert a compact disc into your computer's CD drive.
Import the CD's data into the iTunes library. The iTunes program will automatically ask you if you want to import the audio files on the CD into your iTunes library. Click "Yes" to import the files in the converted MP3 format.