You can find great images on Britannica Image Quest, a database of images to which we subscribe for you.
Access Britannica Image Quest from the library catalog: library.cacegypt.org.
Choose your division and sign in with your Single Sign On. You can also use the CAC Quick Login. (If you do not know it, ask a librarian.)
Once you're logged in, the catalog shows you the home page. Scroll down to the list of databases and click on the link for Britannica Image Quest. If you are logging in at school you will be recognized by the Britannica servers. If you are logging in from home, the login credentials are the CAC Quick Login.
Find an image you like and download to your computer, then upload to your blog with the image button on the blog editor.
Here's a short video tutorial that shows you how to upload images to Blogger.