Find which world someone is on

I don't even know if this is possible, but say I have the name of an account "player1" and he has friends chat set to off.

Is there any way I can get which world he is on?

I don't want to be able to chat with him, or see his dot as a green one, I just want the world.

 

Zezima Stalker v1 is you best bet.
But seriously, the only other way would be to go to the same CC he is in.