If you use Whois. you can get information on the domain (in most cases the full address) of the user who bought the domain as it public unless they got protection to protect there personal details. In which case it will show either the server there on or the place were they bought the domain from as registrar.
I use a software called, HostInfo. It even finds which network is actually hosting the server itself. Like on the whois it might say your website is hosted by bluehost. But using that software you can even find where the server is hosted, for example theplanet.com.