First you need to highlight your audio from beginning to end, then go to file>>>bounce to>>>disk. A pop up menu then should appear with a few different options. One of them is file types, you can either choose WAV. or MP3. If your going to be putting in on a CD choose the "resolution" to be 16 instead of 24. There's also an option to "convert during" or "convert after", Convert during takes less time, doesn't really matter which you choose though, and then click bounce. Pro tools bounces in real time so it will play your song in it's entirety and convert it. It will ask you for a place to save it and to name the bounce, so put it somewhere you can find it like your project folder. Then you should just be able to drag and drop it into Itunes.
You now have a separate bounce file that's in either WAV. or MP3 form and your original PT files that you can still open and mix/edit. If any changes are made in the original just make sure you follow the process again and make a separate bounce.
