If it is an adsl broadband supplier (as opposed to cable NTL or Telewest), then an adsl wireless router is what you want (with built in adsl modem), I would recommend the Belkin F5D7632UK OR NETGEAR DG834G.
<<< is there a lead from the router to the Base station pc? >>>
Sounds like you are talking about internet connection Sharing which you DON'T use with a router. PCs/laptops link directly to the router either by ethernet cable or by wireless, the choice is yours.