Buy PCI usb card.
Disconnect the power to your computer, remove the side of the case. Remove the screw from a blank pci socket cover, (retain the screw) fit the usb pci card in the slot. Make sure its inserted firmly put the screw (the one you previously saved) in and tighten .
Put side of case back on, put screws back in, reconnect power, Windows XP detects the new hardware and will install the drivers and away you go...
