Another great source of information is Netcraft. You can visit their site at http://netcraft.com. Start by searching for your target in the "what's that site running?" textbox as shown in figure.
            
Netcraft will return any website it is aware of that contain your search word. For example,we are presenting with two sites: compterweb.ooo,www.computerweb.ooo. If any of these sites have escaped our previous search (i.e computerweb) it is important ti add them to our potential target. The returned result page will allow us to click on a " Site Report". Viewing the site report should provide us with some valuable information.
The site report provides us with some great information about our target including the IP address and OS of the web server as well as the DNS server.