The newsgroups you're referring to are known as Usenet. These newsgroups date back well before the web became popular. There is no owner per se, though there are procedures for creating new groups.
If you go to
http://groups.google.com, you'll see a web-based interface to Usenet. There's a brief description for each category. You can click on a category to browse subgroups. For example, if you click on rec, it takes you to the rec subgroups. From there, you can click on rec.gambling and then rec.gambling.sports if you want to visit that particular newsgroup. You'll see what I mean.
Google is just one of many interfaces to Usenet. I haven't read Usenet regularly in years, so I'm not sure what the popular interfaces are nowadays. But this will get you started.