I do not have any rights besides Read for this SharePoint site. Is there a way to find out who the administrator for it is so I can let them know a user needs access?
The user that doesn't have access should browse to the site where the Access Denied error appears. On this page they can click a link requesting access and fill in a text box where they can explain why. Once submitted this message will go to the SharePoint administrator.
See this article on Office Online for more info and screenshots.