Many fans are trying to get on the Pottermore website without success, it took a while but the page finally loaded for me. Fans who aren’t able to gain early access will need to wait until the official opening in October. Below you will find a screenshot of the current home page, click it to see it full size.  It reads:

7 books, 7 days, 7 chances
Those of you who would like the chance to gain early access to Pottermore must find The Magical Quill, and then submit your registration details. Each day, from 31 July to 6 August, a clue will be revealed here. Solve the clue and you will be taken to The Magical Quill. Be quick, The Magical Quill won’t be there for long and registration will only be open while spaces are still available each day.

There is also a help page with information about The Magical Quill, you can read that information in the screenshot below. Click it to see it full size so you can read!