Or basically you can search to find out who owns a domain name. Just click on the link below and enter in the domain name you are interested in (without the www. part) click the button and the details will be displayed.
When purchasing a domain name you have the ability to hide details in a WHOIS search – therefore if you cannot see anything other than the registrant (name or company name) – then they have hidden the details and that is all you can see.
If you want to purchase a domain name that is already being used, this will tell you who to contact to purchase it from – or even when the domain expires so that you can pick it up when it comes back into the mass market.