D-Link DSL-G604T 54Mbp Wireless ADSL Router w/DWL-G122 USB Adapter £76.71 click here. This is router with ADSL modem buildin (throw away usb modem you got from your isp). One usb adaptor is for one PC.
For another PC, you can get either a usb wireless adaptor or get a PCI wireless card (D-Link DWL-G520+ AirPlusXtremeG+ 54Mbps Wireless PCI Adapter £28.20 click here).
The laptop should have wireless capability, if not you can get a usb wireless stick or PCMCIA wireless card D-Link DWL-G650+ AirPlusXtremeG+ 54Mbps Wireless Cardbus Adapter £23.55 click here
You can get cheap equipment from other manufacturers by search around.
For cable BB, you need a different router (cheaper) D-Link DI-624+ 54Mbps AirPlusXtremeG+ Wireless Broadband Router £51.44 click here
Better to use all equipment from the same manufacturer, easy to set up. Mix stuff from different manufacturers will definitely work, but need some tweaks sometime.