OK, so that isn't true. But I do have an awful lot of them.
In addition to the obligatory dictionary (in English, Latin, and Lakota) and thesaurus (English only), I have books on punctuation, an AP Style book, and a copy of Jeff Herman's Guide to Publishers Editors and Literary Agents.
I have some great books filled with writing prompts and I've even been known to use them! I also have most of the Writer's Digest "Howdunit Series." Those are full of information, though I wouldn't recommend reading Deadly Doses: a writers guide to poisons at the dinner table. It seems to make the other members of the family a little leery.
One of my favorite writing books, however, isn't a book on writing at all. Michael Largo's Final Exits: The Illustrated Encyclopedia of How We Die is a source of inspiration when looking for "the perfect murder." For example, there have been 18,983 foot-related fatalities since 1975. My personal favorite, though, states that in 2003, twenty-four people died from inhaling popcorn fumes. I'm not sure how I will ever use that bit of information, but I hope to find a way!
Which writing book could you not do without?