As you develop your podcast, you may find that you want to include music, sound effects, or other audio clips to add depth, variety, or emphasis beyond what you are able to record on your own. Here are a few resources to help you find Creative Commons and Public Domain audio files that can be used free of charge (though sometimes with conditions related to attribution and non-commercial use, check here for more details on the different types of Creative Commons licenses).
To learn about Fair Use in podcasting, please see this article by Patricia Aufderheide and Peter Jaszi or contact the Library Copyright Office.