Port replicator = docking station. It's a piece of plastic you set your computer in, plug the cords into the docking station, and the station sends everything to the computer. Mostly it's used to let you easily connect and disconnect your laptop to a monitor and external keyboard.
Google the computer's model, the maker, and the words "port replicator" or "docking station". If the computer's a few years old, your best bet is Ebay. Otherwise check the maker.
Do you know if there is an adaptor that will fit on the back where it plugs in to keep it more secure?
I don't think I really need the port replicator setup.