There are organizations that are called registries that manage each TLD option. When you register domain names, you would first visit a domain registrar who would in turn check with the registry that manages that TLD to see if the domain is available. If the domain for the TLD you want discovers that it is in fact available, the registry adds it to their registry and gives you access to it. If the domain has already been registered by another user for that TLD, you will be shown during the domain registration process that the domain isn't available.
Before you sign up for Web hosting and start building a website, you need to buy the domain name where visitors will find your site. Hundreds of different registrars sell domains, so first and foremost, know that domain names work the same no matter which registrar you use. You don't need to buy your domain from the same company that will host your site. Aside from picking a registrar -- and, of course, your site's name -- you also need to pick a top-level domain like .com or .org.

Keep in mind that these are the highest value cash only sales that have been reported to us in the past week. This column is meant to be an educational tool, not a complete list documenting ALL high value domain sales. Such a list is impossible to produce because many sales are kept private at the insistence of buyers, sellers or both. Our procedure for verifying the accuracy of domain sales reports is available here.

I’ve tried to be charitable to Verisign in my reading of Site-Finder-gate. Even then it seems quite clear that they were deep within the grey areas of their contract with ICANN, and that they knowingly acted against the spirit of the Internet that they’d been entrusted to build. That said, I respect the hustle — Verisign were, and continue to be, a publicly traded company with a responsibility to deliver value to their shareholders, and this quasi-bait-and-switch was a pretty inspired way to do it.
NameCheap offers domain names to individuals and businesses, including a wide range of new TLDs that can draw further attention to your particular business segment. They also have a user-friendly control panel for buying domain names as well as offer hosting and tools for building your website. I personally used them to transfer over 25 domain names at once, and it took a few days and about three clicks. They're my go-to processor for names I'm just looking to hold.
The root is the upper-most part of the DNS hierarchy, and involves delegating administrative responsibility of “top-level domains”, which are the last segment of a domain name, such as .com, .uk and .nz. Part of our tasks includes evaluating requests to change the operators of country code domains, as well as day-to-day maintenance of the details of the existing operators.
Registrars offer a wide variety of registration durations—one year, three, five, and even ten. Be careful about registering for more than a year, though. First, there might be restrictions on your ability to transfer the domain name should the registrar give poor service. Second, the registrar could go out of business, leaving your domain name without a host. Check the policies closely.
Under no circumstances should you pay more to transfer a name than to get a new one. Check what the transfer will require. Does the new service handle the task completely? Or do you have to go into your current registrar's site and change the technical details manually? Finally, check the transfer policy of the registrar before registering your domain name.
In order to register any domain, you must provide certain personal information that you may not wish to be publically searchable in the Whois database. Signing up for WhoisGuard is a great way to keep your registration data private. WhoisGuard acts as a "shield" for your searchable information, displaying the address, phone number, and email of the domain registrar (Namecheap, e.g.) instead of your own. Keep in mind that WhoisGuard is an optional security add-on that must be renewed separately when you renew your domain.
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