In order to remove DRM protection for free, you will need iMovie - iMovie is a separate application, the current iteration of iMovie released with the iLife '08 software bundle is iMovie 1. You can download iMovie at Apple - http://www.apple.com/support/downloads/imovie714.html.
Tips: With iTunes you can import your local files into iPad, iPhone or iPod for reusing. For example, Mac users can use Text to ePub for Mac to change your editable text files into ePub format for transferring to iDevice for reading at will.
Step 1. Make sure you have installed iMovie first, then start iMovie and 'Create a New Project' titled 'DRM-free', then save the project to your Desktop.
Step 2. In the iMovie window, select the 'Media' tab located between 'Themes' and 'Editing'. You will notice that the top right portion of the interface now offers a media browser. Select the 'Audio' tab and locate the playlist which contains purchased music, or search by artist / title.
Select the DRM-laden song and drag the file from the media browser into the iMovie timeline where it says 'Drag audio here to build your project.'
Step 3. In order to export the song, iMovie requires that a visual image be associated with the audio track. Simply drag a blank image (or any other image as you like) to the track above the previously imported audio file.
Once iMovie has processed the image, select the 'Share…' sub menu item from found inside 'Share' in iMovie's menu bar.
Step 4. Select 'Expert Settings' in the 'Compress movie for:' drop-down menu, for selecting 'Expert Settings' mode will provide the options to export the file as an audio file. Then click the 'Share' button.
Step 5. In the 'Save as' dialogue, select 'Sound to AIFF', in the Export drop-down menu, choose an appropriate directory for iMovie to export to, input title and 'Save'. iMovie will compress and export the movie project as an audio file in 15-40 seconds, it depends on your machine configuration.
Locate the exported AIFF audio file and drag to your iTunes Library, then right-click on the file and select 'Convert Selection to AAC'. Once completed, 'Get Info' on the new file, add album art, done.
Congratulations! You have done that! Just enjoy your music!
How to remove DRM from iTunes M4V, WMV, WMA and convert protected media files?