If you use Hey Homepage as a service: A domain name of your preference and one email address are included in the service. Some special domain names increase the monthly fee. If you already have a domain name, the monthly price drops.
Need more email addresses? You can add an extra email address for a low fee. See the prices overview for more information.
If you buy a license for the source code of Hey Homepage: You take care of your own domain name and email address(es). You can get them together with the hosting at most webhosting companies. It's also possible to register a domain name at one company, and connect it to your webhosting at another company.