Welcome to the discussions, bobandearl.
When you use the word "iTunes" to describe the music files what exactly do you mean? If you mean songs you have purchased from the iTunes Music Store (iTMS), then you must first burn the songs to an Audio CD and import them as MP3. This Apple KB article can help you:
How to Burn an Audio CD in iTunes for Mac.
If, on the other hand, you are refering to songs you have imported to iTunes from commerical CDs the easiest way will be to convert those songs to MP3 files. Again, the Apple KB can help:
iTunes: How to convert a song to a different file format. You can also re-import the songs from the original CD.
(FYI: songs purchased from the iTMS are protected, 128Kbps AAC files and cannot be directly converted to another format in iTunes.)