before you go wireless you need to answer one simple question - do you want your slave pc to be able to access the net independantly of the master PC? If no then you need 2 wireless adapter cards one in each PC I have fitted this set up on a number of ocassions normally when parents want to control their kids access to the net. If yes then you will need a wireless modem/router (I use BT Voyager 2091 and its fine)and a wireless pci expansion card (d-link is fine but there are loads). Both the modem and router you can get on e bay without too much expense. Connect the router to your master PC via an ethernet cable, set it up iaw the instructions (dead easy) and you're on the net. Set up the security side of it iaw the instructions using a password (again dead easy). Fit the pci expansion card to the slave pc, set up the security using the same password and thats it. You then have a secure wireless system. If you need more post back.