Boorstin, Jon, Making Movies Work:Thinking Like a Filmmaker
Also helpful for thinking about how and why a reader enjoys a novel or memoir.

Butler, Robert Olen, From Where You Dream: The Process of Writing Fiction
Brilliant.

Field, Syd, Screenplay: The Foundations of Screenwriting
Excellent for plot.

Gardner, John, The Art of Fiction: Notes on Craft for Young Writers
Forget the subtitle, "for young writers". This is a book for writers of any age, and not necessarily beginners. The chapter "On Common Errors" is a gem. Also highly recommended for writers of creative nonfiction.

Gerard, Philip, Creative Nonfiction: Researching and Crafting Stories of Real Life
Writing a memoir or a longer, more thoughtful piece of journalism? Use this book as your project's road map.

Goodman, Richard, The Soul of Creative Writing
Highly recommended, especially strong on language.

Hills, Rust, Writing in General and the Short Story in Particular
The best book I've found on writing short stories.

McKee, Robert, Story: Substance, Structure, Style, and the Principles of Screenwriting
A profound book about narrative structure, also useful for writers in other genres, including the short story, novel, creative nonfiction, and more.

Oliver, Mary, A Poetry Handbook
This one is short and sweet. Finally, an articulate answer to the question, Why is a rock not a stone? An excellent resource for poets, as well as prose writers, who should never – ever – underestimate the importance of the poetry in their prose.

Piercy, Marge, and Ira Wood, So You Want to Write: How to Master the Craft of Writing Fiction and the Personal Narrative
The chapter on dialogue is the best I've read yet. My workshop students praise this one highly.

Prose, Francine, Reading Like a Writer: A Guide for People Who Love Books and for Those Who Want to Write Them
Divine.

Ricco, Gabriele Lusser, Writing the Natural Way: Using Right-Brain Techniques to Release Your Expressive Powers
The first and biggest barrier to writing quality literature is your Left Brain, or your "Sign Mind." This book shows you how to quiet the Sign Mind and let your Design Mind emerge to play.

Scarry, Elaine, Dreaming by the Book
Essential for understanding how and why specific sensory detail "works" to create a vivid picture in the reader's mind

Sims, Norman, and Mark Kramer, editors, Literary Journalism: A New Collection of the Best American Nonfiction
A bit dated now, but nevertheless an outstanding selection. The introduction on the art of literary journalism (the more fashionable term these days is "creative nonfiction") is vital.

Smiley, Jane, Thirteen Ways of Looking at the Novel
Includes her reviews of 100 novels. This is a treasure of a book by one of our greatest contemporary novelists.

Wood, James, How Fiction Works
Glorious, delectable, and practical.

Zinsser, William Kowlton, On Writing Well: The Classic Guide to Writing Nonfiction