ICANN publishes the complete list of TLD registries and domain name registrars. Registrant information associated with domain names is maintained in an online database accessible with the WHOIS protocol. For most of the 250 country code top-level domains (ccTLDs), the domain registries maintain the WHOIS (Registrant, name servers, expiration dates, etc.) information.
In the first quarter of 2015, 294 million domain names had been registered. A large fraction of them are in the com TLD, which as of December 21, 2014, had 115.6 million domain names, including 11.9 million online business and e-commerce sites, 4.3 million entertainment sites, 3.1 million finance related sites, and 1.8 million sports sites. As of July 2012 the com TLD had more registrations than all of the ccTLDs combined.
If you've ever been worried about the tremendous amount of power large data centers consume, you might want to sign up with Green Geeks. The "green" in the company's name reflects the Green Geeks' commitment to the environment. It purchases three times the energy it actually uses in wind energy credits, essentially putting energy back into the economy. The company does this through a form of renewable energy certificates, which, while a bit complicated, means that it's not just energy neutral, i's actually helping fuel the green energy economy.
Domain names used in works of fiction have often been registered in the DNS, either by their creators or by cybersquatters attempting to profit from it. This phenomenon prompted NBC to purchase the domain name Hornymanatee.com after talk-show host Conan O'Brien spoke the name while ad-libbing on his show. O'Brien subsequently created a website based on the concept and used it as a running gag on the show.
But, again, operationally it's quite strong. 24/7/365 customer support is available not only by live chat and email, but by phone. It offers free site migrations with some dedicated attention paid to making a transfer as smooth as possible. And, if you're willing to go for one of the higher-end plans, the company has put some serious attention into performance and caching.
^ March 16, 1992 memo from Mariam Leder, NSF Assistant General Counsel to Steven Wolff, Division Director, NSF DNCRI (included at page 128 of Management of NSFNET, a transcript of the March 12, 1992 hearing before the Subcommittee on Science of the Committee on Science, Space, and Technology, U.S. House of Representatives, One Hundred Second Congress, Second Session, Hon. Rick Boucher, subcommittee chairman, presiding)