J.K. Rowling’s Pottermore website that lets Harry Potter fans explore the books’ universe and interact with other fans has finally opened registration for anyone who wants access.

Pottermore was announced last June as a site where Potter fans can read new content about the Potter universe and as an online shop to purchase the books in e-book format. At the end of March, the site finally made it possible to download those e-books, which generated $1.5 million in sales in just a few days. That shows people are still firmly interested in the Potter books, even though the series concluded in book form in July 2007 and in movie form in July 2011.

The Pottermore site has been in limited beta since it launched, but many other Potter fans (including myself) have wanted access to see if the site might shine a light other aspects of the books’ universe and mysteries. I tried registering earlier today but after confirming my e-mail address, the site said, “We’ll send you an email to let you know when you can explore Pottermore.” The site chooses a random user name for its users to protect children.

A blog post from Pottermore indicates users will be approved in waves. It notes: “Over the coming days, we’ll be inviting new users onto Pottermore.com. We’re expecting to be really busy to start with and plan to activate new registrations in a steady stream. This means that you may not get access to Pottermore immediately after you sign up but we will get you exploring the site as quickly possible.”

Those who get access will first be sorted in one of the four Hogwarts houses by the Sorting Hat and then be able to explore the mythology of the Potter universe. Rowling has written 18,000 words of new material for the Web site about characters, places, and magical objects. The site also promises social games and the ability for fans to share their own Harry Potter stories.

Take a look at a sneak peek video below for more on Pottermore: