You can use a graphics search engine, such as Yahoo's Image Surfer to find a specific graphic. Not all graphics on the internet are copyright free. If you see a picture or graphic on someone else's web page, you should ask for permission to use it in your web page. Most web pages will give you the e-mail address of the organization or person who made the web page. E-mail a message to them requesting permission to use their graphic, explain that you are a teacher creating educational materials for use in your classroom.
Many people are generous when something is to be for educational purposes.
Store all graphics in this folder.