Have you ever thought the websites you visit frequently or daily who own them,where are they hosted,how old is the domain name.Incase you got a website and you need to contact the owner if there is no contact us or support page on the website then what you will do?You can lookup for the whois information of the website which gives you the detail about the website.Incase anyhow you find a suspicious IP and need to lookup for the information about the IP like from which country it belongs and the ISP then also you can lookup for the information.
Here are two websites that I personally use first one is
On this website you can look up for the domain or IP whois information apart from this they have other tools as well like traceroute etc,it also shows your public IP on top left corner with your location according to the IP.I only use the site for whois information but they do have other paid features as well that I never tried.The only drawback of dnsstuff is that they dont provide whois info for a domain ending on .me extension so I jump to my next choice for this to Network Solutions whois link
http://www.networksolutions.com/whois/index.jsp
Network Solutions is also a domain registrar and hosting provider with much more services but I only use WHOIS lookup on their site that gives info about any domain name or IP
Just make sure to select the appropriate option on the right side of the whois lookup bar whether you are looking for a domain whois or an IP information.Recently they started another service using which you can directly see the details of a domain in your browser by using the format
www.networksolutions.com/whois-search/netsol.com
These two sites help in finding the detail information about any website or IP incase you wanna know how old is any website and other information.
PS: All domain registrars provide a facility of private registrartion for a small fee to prevent personal information from hackers, spammers and even data miners so if someone is using that feature you cant see anything apart from the domain age and the servers where it is hosted and furthur if someone is using private nameservers that is provided by webhost for an additional charge then also one more limitation comes