You can buy for about £50 an ADSL modem, Router, with USB and ethernet ports.
This is what I use and can have upto 4 PC's online simultaneously.

For your laptop, I would recomend an ETHERNET PCI interface if you dont already have one.
(This should be about £40)
This will allow a longer wire length from the router plus should be the quickest.
(100 megs per sec)

Try this link for an example
http://www.misco.co.uk/productinform...EWAY/index.htm

I recomend asking the company you buy these products from for their advice before purchasing
just to be safe !