When you are looking for clips and stock photos to use in your projects, it's good to get in the habit of finding files you can use without violating the original creator's copyright. This guide provides a list of a few places to get started when you need to find video, images or audio. There are definitely more places out there -- try searching online, but be careful to check the information each site provides about the licenses governing the media. (For example, many files that might be free for you to use personally or for educational uses are NOT free if you are creating something that will be used commercially.) Not sure if you understand a license? Check in with a librarian, and we'll try to help.
The following codes of best practice can also help you determine if your use of copyrighted items falls under the fair use exceptions of the Copyright Law.