Here are some informative links to get started and understanding some aspects of copyright.
Everything on the Internet is not true and like this, everything on the Internet is not free for you to use.
Copyright protects digital items just as it does physical ones. However, in the digital environment it can be very difficult to see what copyright or license applies and even more difficult to track down a creator to ask for permission. Consider the following four items.
1. Use media with stated licenses.
This includes Creative Commons and Public Domain; these works will be clearly labeled so that you understand what you need to do to edit or reuse them. This does not take away the need for giving credit where credit is due though. Attribution is part of Creative Commons and items will typically state this.
2. See if your situation qualifies as Fair Use.
If you are using these materials in the classroom, as a student or instructor, your work may be subject to different guidelines. Remember, you will still need to provide citation information to give proper credit to your sources. When considering Fair Use, think about the academic use of what you are doing.
3. Create your own media.
Thanks to technology, creating your own images and media is easier than ever before. Use a camera, audio or video recorder to make your own media.
4. Purchase the rights to use items.
There are many sites where you can pay to be able to use images, videos, etc. Most consider pursuing the other three options first!
Guidelines for Best Practice (the following are not legally binding)
"The code identifies eight situations that represents the library community's current consensus about acceptable practices for the fair use of copyrighted materials and how those rights should apply in certain recurrent situations." Click on Code of Best Practices in Fair Use and Academic and Research Libraries to download the document.
"Created by the International Communication Association. Helps U.S. communication scholars to interpret the copyright doctrine of fair use."
"A code of best practices that helps creators, online providers, copyright holders, and others interested in the making of online video interpret the copyright doctrine of fair use. "
In order to use audio, video or images, you should have a basic understanding of the terminology many of the sites use with regards to usages and rights. These are a few terms that are important to be familiar with when dealing with content.
Definitions adapted from: Black's Law Dictionary, 8th Ed., Edited by Bryan A. Garner, published by Thomson West (1999) & Creative Commons (http://creativecommons.org)