How do you search the log history for a certain web address?

i heard you can check all the ips that logged into a certain web address. it is supposed to be one of the ways you can find out someone's ip address, getting them to log into a non-existent web page and then checking the log history of that webpage to find out their ip. but i don't know how to search the log history. anybody know how to do that?|||that depends if the website itself is storing the IP address of the visitor. if you are only a visitor and want's to find out the IP of other visitors, it is impossible.