www.pottermore.com
To find The Magical Quill you need to solve the clue and add the answer to the end of the web address http://quill.pottermore.com/
This will lead you to a website where The Magical Quill will be located while early access places are still available. Once you have found The Magical Quill, you need to submit your registration details on Pottermore before registration closes for that day.
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"I can be friendly when I desire to. Alas, desiring to be more intelligent does not make it so."