Customize web addresses
You can make it easy for users to find your Google services or a web site you build with Google Sites, by customizing the web address they type in their browser. That way, all they have to type is mail.yourdomain.com, or www.yourdomain.com, or just plain old yourdomain.com (using, of course, your actual domain name). Customizing a web address is easy but it does involve changing your domain's DNS records. You access these records at your domain host, not with Google. See below to find out how.