Well, it looks like there is a complete fanfiction version out there, from the language it would seem to be written by an american. This is the file I found most often. It might be a good story, but it does not have the feel of a genuine HP story (just read the first few lines).
There is another, incomplete version out. It is not so widely spread but it looks more genuine...who knows...might be the real deal but not complete or and earlier draft...or something completely different.
the only question is...will I read it?
I found a funny quote from JK Rowlings publisher claiming that this book "will not land in the internet like the others"...a strange notion if you ask me...if it's printed somebody will scan it...ever tried to DRM a paper-book?