The Book of Mazarbul, from Tolkien.
The iron-bound Book of Skelos, from Robert E. Howard.
The Journal of the Whills, from Star Wars.
http://en.wikipedia.org/wiki/List_of_fictional_books
http://en.wikipedia.org/wiki/List_of_fictional_books_from_non-print_media
http://en.wikipedia.org/wiki/List_of_fictional_books_from_periodicals
Wiki has a few more variations on the theme.
Whole Art of Detection, by Sherlock Holmes (And any of his monographs or essays you might find laying about).
The Nice And Accurate Prophecies of Agnes Nutter, Witch
A Young Lady’s Illustrated Primer
Also, I know there are a lot of them out there, but as many versions of the Encyclopedia Galactica as you can find.
Hamster Huey and the Gooey Kablooie, and its sequel, Commander Coriander Salamander and 'Er Singlehander Bellylander.
The Princess Bride: S. Morgenstern’s unabridged original text. Goldman took out all the good political satire.
I would like finally to read an account of Sherlock Holmes’ adventure involving the Giant Rat of Sumatra, which Holmes mentioned in passing once to Watson but withheld any further details as “the world is not yet prepared” for it.
A “real” volume of The Neverending Story might be interesting too. (A blatant case of false advertising, as Lionel Hutz noted on The Simpsons)
The Giant Rat of Sumatra: at last the world can know!
I’d probably need a cage first, but I’d like to capture a copy of The Monster Book of Monsters. It was on a textbook list for Harry Potter
You’ll need the concordance, or it’ll make no sense.
I want Sceltie Saves the Day and Unicorn to the Rescue. Plus (plebeian, I know), I’d like a complete, finished Mystery of Edwin Drood.
Susanna Clarke’s masterful Jonathan Strange & Mr. Norrell includes quite a few fictional works in its voluminous footnotes: Susanna Clarke - Wikipedia
Jake Sisko, son of the commanding officer of Deep Space Nine, was a journalist and wrote poetry and fiction - just one novel, Anslem, that’s mentioned, though: Jake Sisko | Memory Alpha | Fandom
In Sandman, there’s a dream library - a lot of titles are shown in it.
The Library of Dream - Beachcombing's Bizarre History Blog has their own version - maybe it will give you more ideas 
Well, since it is almost Halloween, The Philosophy of Time Travel by Roberta Sparrow.
Paul Sheldon’s Misery Chastain series and Fast Cars
Where God Went Wrong by Oolon Colluphid
Some More of God’s Greatest Mistakes by Oolon Colluphid
Who Is This God Person Anyway? by Oolon Colluphid
Well That About Wraps It Up for God by Oolon Colluphid
The Octavo
Turns out all those books were ghost written by Richard Dawkins.
East of Eden, by John Steinbeck
A Painted House, by John Grisham
The Pillars Of The Earth, by Ken Follett
The Winds Of War, by Herman Wouk
Texas, by James Michener
Shogun, by James Clavell
The only reference I could find on Google re. your statement is that Oolon Colluphid was a character based on Richard Dawkins by his friend Douglas Adams. You might be right, but I’d appreciate a source.
But surely it contains perfectly common words people speak every day; what makes a word spoken “from” the book?
I’m sorry, but this is either a whoosh or way too intellectual for me. Could you please expound on your choices?
As for additional books, I think I should include a copy of Fireside girls Handbook.
I’m not sure if The Death Note counts a book for this purpose.
Peace - DESK
I had three or four jokes I almost made, but yours was better.