Yea man.
Depending on the version of iTunes you're using, you could either Right Click the song in your iTunes list and choose "Create AAC version" and then when that's done, you right click on the newly created song and choose "Show in Finder". Change the filename extension from M4A to M4R. Override the are you sure prompt and save. Once it's done, double click it and enjoy.
(In the newer version of iTunes the option is in the drop down menu under FILE - Convert.)
Cheers.