I have never heard it called a nook before. I'm sure there are patterns for covers free online. Try this one (I just googled kindle cover free pattern)
http://www.chicaandjo.com/2009/09/03...le-cover-case/
I kinda like this jeans one at:
http://hubpages.com/hub/Kindle-Covers-For-Free
Jeans Kindle cover
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