To know the contact information like domain owners, admin or technical contact this tool helps you. Also you can see some technical information about that domain or website like the nameservers the domain uses, number of websites hosted on that particular server/IP and other nice information.
You can also see the domain name registration dates and expiry dates. Every webmaster would find this tool very useful. You can find this at Who Is Domain Tools where you need to enter the domain name or the IP address.
I just made a search there for Google.com and i found interesting info on its name servers and registration dates :)
You can also find the number of servers hosted along with Google.com. Note that this is for informative purpose only.
