I used the example site.xml file found at Creating a site page. Then I edited the links (those will show up in the top right if I am correct) and changed the menu to what I needed/wanted.
The line
<menu ref="reports"/>
will put a second menu on the left containing reports that are generated by the maven-site-plugin that is named Project Documentation by default.
Be sure to delete the three dots (...) before the closing tag for the body element as they will give an error on creation.