En example?
Ok. Try a whois on 212.181.92.132. You will get not only the address, but the correct building (and incorrect person, but it narrows it down to about 5 people).
To prove the opposite, just look up any ip in the 213.65.0.0 - 213.65.255.255 range. You will get the exact same reply for the entire B-class network whichever IP you lookup. Thus it has nowhere near the detailed mapping of the first example.
Thus, sometimes you can find out almost everything from just an IP. I rest my case.
/Egon, x3guide