ITPFacebookLikeBox is a module for Joomla! that adds a fan box on the website. This is a documentation and guide of the extension. You will find answers to some questions and how to set it to take full advantage of it.
Which URL do you have to use?
On Facebook, there are many types of pages - groups, fan pages, profile pages, ... This widget is designed to work only with fan pages. So you need to enter in the option box for "page URL" address of your fan page.