A combined ADSL modem/router, like the one you linked to, would be ideal.
Plug the phone line into the back of the router, and each PC to the front.
Just like a hub, but with shared BB access. You don't need any more network cards, as you must have one in each PC to connect to the hub.
Forget USB - it can be made to perform networking, but even the people who invented it discourage its use for networking purposes.
BTW, you can also connect the hub to the router, to give even more connections.