Fallout Tactics' multiplayer mode doesn't use any "server". It is hosted on a player's computer, for the time of a game, using softs like Hamachi or (more frequently) GameRanger. Approximately one year ago there used to be games hosted on GameRanger quite often, I don't know if it's still the case.
You'll need the 1.27 patch to play, though. It is designed to work only on US versions.