How do you find who hosts a website

You can do a Whois lookup on their domain name and generally find the name of the hosting computer. It's the one that reads ns1.somewebhostnamehere.blah. Sometimes you'll have to take that, without the ns1 part and plug it into a search engine to find out what that company name is. If they have a privacy protected domain name, you may not be able to locate any information about where they are hosted.