While surfing on the internet I came across a site www.trackmylaptop.net which provides the service of tracing a stolen laptop. Its a free of cost service offered by Quick Heal to all the laptop users in India (who may or may not be using Quick Heal). You just have to provide the MAC address of your laptop and this service checks into its database, and if some record is found then it gives you the ip address and the city where the stolen laptop is being used ! Also if you are purchasing some second-hand laptop then you can check whether it is a stolen one or not. But this works only if you know the MAC address of your stolen laptop !!! Visit the site for more information.