In addition to the Content Manager, which can be accessed via the Media Element, there are a wealth of resources available to obtain stock images to use with your website.
Some offer completely free photos for you to use, some will offer free subscriptions, and some will offer paid memberships. It's best to preview a few different options and select the one that works best for you. Below are a few favorites of the LiveEdit staff.
Please Note: The use of copyrighted materials on your website is done at your discretion and you are responsible for obtaining proper permission. Any issues resulting from the use of said materials will be your responsibility.