Perform a "Whois" check on the domain of a website. It should return many details that a webmaster must give about himself or herself to register that domain (and most of the time, the domain owner is the web master). You can use these details to contact the webmaster.
Performing a Whois check is easy - just go to a Whois-check website for an easy check. [ http://www.betterwhois.com/ ] is a good option - just type in a domain, and it splurts out any information it has.