You can also use VLC to convert .ra files:
1. Go to File Menu and select Convert/Stream
2. Choose the .ra file to convert by clicking the Open Media button, or dragging and dropping the file onto the designated area of the VLC Convert & Stream window.
3. From the Choose Profile pop-up menu, choose a the format you want to convert to (Audio - mp3 for example)
4. Click the Browse button, choose a location to store the new file, and give it a name, including the file extension (.mp3 in this case).
5. Click the Save button to complete the process.
You can now open the .mp3 in iTunes, or other software.