The middle of the room or the closet, doesn't matter to me! Although Rose would have to have a pretty huge closet. XD

I think it'd make more sense for the Doctor to find out via an incident or newspaper or TV or hearsay or something. I can't think of any circumstance where the TARDIS actually gave the Doctor a tip about anything. He'll immediately know what's going on though -- the Nestene Consciousness and the Autons are directly lifted from the first episode of the Third Doctor -- right down to the walking mannequins with the guns in their hands. XD