As promised, here’s how to change your MAC address in Windows Vista (this method will hopefully also work in Windows 7).
Go to Start -> Control Panel -> View network status and tasks -> Manage network connections (in the left sidebar).
Choose the connection for which you want to change the MAC address, right click on it and select “Properties”.
Click on the “Configure” button and go to “Advanced” tab. In the “Property” box look for “Network address”. Now you should see a window like this:
Instead of “000000000000″ fill in your desired MAC address and press “OK” button. Open the command prompt and check that the MAC address got changed:
ipconfig /all