It should be as simple as just dropping a CD into the CD drive on your computer and then dragging files to it and you get the option to create an audio CD. But clearly this didn't work for Julie. I has a program called Toast which allows me to quickly create audio Cds.
But if you don't have a program like that and you just want to use the functionality built into the Mac it's certainly easy and possible. This is another place where as they say "Google is your friend". I search for "burning CD Mac OS X" and immediately found an article showing exactly how to do it.
I don't want to tell you don't call us the questions because we're happy to answer questions but generally if you can figure out how to pose the question Google or some other search engine will have a simple single answer for you.