One of the simplest ways to find images with Creative Commons licensing is to use a Google Image search and choose the license that most closely matches what you intend to do. Even after locating an image this way, be sure to check the source of the image to verify what restrictions, if any, the creator has placed on its use.
To use Google this way:
What kind of licensed work you’re looking for will depend on how you want to use it. Do you want to simply copy and republish an image on your web page? If your use is noncommercial and you won’t be creating a derivative work, you can use any Creative Commons licensed content as long as you attribute it to the original author. Do you want to edit or remix that image? You’ll need to find a work with a license that does not restrict the creation of derivative works. If the work you want to remix has a “share alike” license, you’ll also need to be sure to license your new creation under the same terms. Below you'll find three examples of resources you can use to find open content on the web.
Search.CreativeCommons.org: A search platform created by Creative Commons that lets you search multiple sites for Creative Commons license images, video, music, and other media based on the type of use you want to make.
Wikimedia Commons: A repository of public domain and freely-licensed educational media content. Everything is free to use, but for all media not in the public domain, you’ll need to check the license and comply with its terms.
flickr: A repository of images and video that allows you to filter your searches for content you are free to use. Using the drop down filter in the upper left corner, you can search for works in the public domain, all Creative Commons licensed images, or works that allow you to make modifications or commercial uses.