I hear there's a novelisation of the 7th guest with several scenes added .

I was wondering if there is a PDF version of the novel floating about.

Let me save you some time and money; the game download from GOG comes with a copy of the complete original script (IIRC; if not, you can find it online). Read that. Now imagine that all of the spooky random crap and the framing device of the story being experienced by Ego are virtually ignored throughout until the very end. Now throw in some spelling errors that any self respecting author should have caught as the cherry on top of the mediocrity sundae.

In all seriousness, if you really want to check it out, I doubt that GOG would really appreciate discussions of attempted copyright infringement on their forums. They are doing a good thing here, and they do not need their users making potential IP licensees concerned that making their games available on GOG will result in them being pirated by the fanbase. If by "PDF version of the novel floating about" you mean one available for purchase, then I have been unable to find one; however, a print version does exist and is available on Amazon.

Okay I do apologies for not making it clear, I did mean where to purchase because while it is all good and nice to have a physical copy in my hand of a novel, I live in the middle of nowhere so Ebooks are a much appreciated time save. 5 minutes to purchase an ebook vs a week+ to wait for a book to arrive.

But it's nice to know that the games script does contain these extra scenes, I thought it'd be a case of the novelization has been expanded to make it long enough to fill a book.

There are two scenes that were deleted for some reason, but you're really not missing all that much.