Need Suggestion: how to Fetch Facebook information using the facebook_id in rails 3.1

Hi,

I am the Newbie to rails and fb_graph.I have a rails3.1 app with
authlogic authentication. all of users can the register with the

facebook_id in my app. what i am suppose to do means if any one user
can see the others facebook profile using the facebook_id. if there is
any possiblity or not.

Any samples like this or some example are available. .

Thanks in advance.