Is it illegal to do this in your state?

[Michael]

Lets say you and a person are talking. The person doesn't tell a girl that he's with at some event and you find out from a third party and the person himself. You don't know who the person is, so you look them up on facebook. Is that stalking? Can you be arrested for it?
*The person doesn't tell you which girl he's with

[racinngfan3]

No it is not stalking unless you continue with your checking up on them

[Bob B]

No. There's nothing illegal about looking up someone on facebook, especially in a situation like this where all you're doing is trying to find out who someone is.

Either way, facebook profiles are made up of information someone voluntarily uploads for others to see, so looking at someone's facebook profile would not, by itself, be considered stalking (in the legal sense anyway).

[Far Beyond Driven]

No, what you said isn't illegal, or even stalking in any state.