Images and music can be powerful rhetorical tools.
Images can inform (ethical appeal) and move (emotional appeal) the viewer.
Music can set the stage and move the listener.
Astute rhetoricians use multiple tools to persuade their audiences.
When you create a presentation, you want to use images and/or music effectively, but you also want to use them legally. You need to choose images and music that are available for non-commercial/educational
use. Be sure to include proper attribution of the image or the music. Check out the resources below to help you find images and music.
Use this list at Wikipedia to get you started -- especially the General Collections. Be sure to follow the attribution directions at the website where you find the image.
Modify your search in Google Images:
On the search results page, click Search Tools, click Usage Rights,
and check labeled for non-commercial reuse.
Search in one of TCA's databases. The citation information will be provided.
Look for music licensed by Creative Commons (CC). Your safest choice is music in the Public Domain or Shared for non-commercial use. Follow the site's directions for attribution.
Here are a few places you can search.