To locate and access Open Source music for presentations, use http://dig.ccmixter.org online.  Unlike much digital music, this site lets you use these songs in their entirety without running the risk of copyright violation. However, you need to give credit through a citation to include the type of license, the artist's name and the title of the track with links and urls.   

  Instructions: 1. Click the dig tab 2. Click blue words "advanced dig" 3. See options for genre, instrument, style. You can make choices under one or all of the options. 4.  Click "dig" 5.  Click a song title to preview 6. See little down arrow to download. 7.Click the little "i" icon and then click on "MORE" at the bottom right to find citation information.