I met someone while traveling. We were into each other but the circumstances did not allow us to exchange numbers or addresses. We met in front of a building while he was waiting for someone and he was ringing a bell on that building. I thought it would be easier to ask the residents about him because clearly he knows one of them. Looking up his number in telephone directories is hard. I know the address of the building, so I just need to know information about the residents so I can ask one of them.

I know how to, but I really don't think it would be a good idea in this case. Are you able to hang out in that surrounding area and hope to run into him?

You don't want to appear to be stalking. If it were me living in that building, I would be very wary of anyone asking questions about a resident.

I'm thinking worse yet since he had to ring the bell it could be a girlfriends apartment building.

Most realtors have a directory by address (I think its called a Coles Directory)

In the U.S. there's this -- Criss Cross Directory | Haines Directory - Criss-Cross.com

There may be something similar in other countries. Check with a library or real estate agency.

Yes, its Coles

I failed to mention that we met in Paris but we both don't live there.

Regarding to tickle's answer, I understand what you mean and I myself not want to appear as a stalker. I've never looked for someone like this and the last thing I want is to look like a stalker to him and others.

I thought about asking the people living there but in an unsuspicious way, but since I don't live there it would be a hard thing to do.

To answer N0help4u, I don't think he was waiting for his girlfriend there because he asked me out while he was waiting and tried to exchange numbers, but I was hesitant at the time and I left before we could talk more. He did mention he was visiting his mother there so maybe he was waiting for her, but I don't think it was his girlfriend or he wouldn't have asked me out on the same night.

Wondergirl and scottgem mentioned Coles directory, Criss Cross directory and Haines directory. As I said earlier, sorry to have failed to mention that the place is in Paris, France, so I do not know if they have them. I would check the libraries in Paris but I am not currently there.
Do you by chance know what substitutes are there in France?

I would think Paris libraries invite email reference questions and would go that route. (Haines = Criss Cross)

Thank you Scott. Your reply has been helpful!