lwcomput says:

That’s like asking for a complete list of everyone who has ever sent an email. It’s virtually impossible to know that. The root servers might be able to create such a list, but even that would not be completely accurate – domains are expiring all the time and new ones are bought all the time.
You want an extensive list? Pick up a dictionary. Just about every single word in the dictionary already has a registered domain owned by someone.

the cookie diet says:

Your’e talking about millions of sites. You could probably buy them but they are maintained by multiple companies.