How to connect to the internet through another laptop

Hi,

I am currently staying in some student accomadation, and have paid a significant amount for an internet connection, however I have multiple laptops and they are telling me that the only laptop that can access the internet is the one which I used to register. And they are asking me to pay a small fortune if I would like the other's to be able to access the web. I was wondering what is required (i.e. a router) and what how to config the settings to allow me to acess the internet through the laptop that's mac address is registered with the company. I would not be looking for such a drastic solution however, when I contacted them and requested another laptop to be allowed on the internet and informed them that I would only ever be using one laptop on the internet at any one time they still refused to help, which leads me to believe they are just trying to bleed me for as much money as possible. Both of the laptops are running windows vista. I am grateful for any assistance anyone can provide, I have an alrite understanding and knowledge of computers, however when it comes to networking I am useless so if you could keep the response 'dumbed down' , would appreciate it very much. Thanks.

thank you very much