You must have SSL installed on your site for your page to show within Facebook. If so, just run Autotune in JFBConnect and look at the "Namespace" setting in the Application tab. Then, go to:
apps.facebook.com/
For example:
apps.facebook.com/joomla-extensions
That should be it. There are more settings you can use for a specific template and such in the Page Tab / Canvas configuration area of JFBConnect as well.
I hope that helps,
Alex 
Site in Facebook
