You can see who likes pages or is a fan of a page and send them messages or friend requests.
Click on Pages on the left part of the window (the sidebar). Then select a page in the main window.
Click the contextual menu button.
Choose Show Likes.
The main window now displays people that like that page.
You can now select anyone in the main window and view their friends as well.
Some pages have privacy settings that disallow others from viewing their likes, in this situation no one will be listed in the main window.