Write Screenplays That Sell -- the Ackerman Way
by Hal Ackerman
Highly Recommended by Coverage, Ink. as the go-to all-purpose book on screenwriting. If you only buy ONE book on screenwriting in your life, THIS should be the one.
This excellent book is a must-read for anyone planning on making a go of it as a screenwriter in Los Angeles. Not a craft book, but rather a rules of the road and savvy survival guide for writers.