I recently took a course with Robyn DeHart about "Revising using GMC." Robyn did a good job explaining GMC to those of us who hadn't read the book or taken any GMC courses, but my befogged brain needed more. So I singed the poor old Visa card again and bought Debra Dixon's Goal, Motivation & Conflict: The Building Blocks of Good Fiction that Robyn often referred to.
Even though I've only read up to the 'Goal' section of the book (Chapter Two) so far, I can already tell this is going to be one of those books to be kept close by and referred to often. It's an easy-to-read, easy-to-understand reference book - one that doesn't make my head spin. It's all information I 'sort of' knew before, but the clarity of it, and the examples and charts Debra gives helps solidify the premise in my mind and give me a base to jump from when plotting a new story.
Side note: I looked it up on Amazon.ca ($137 and up) and Abe Books and Addall Book Searching ( $84 and went up as high as $222). If you want to buy the book at a reasonable price, buy it directly from the publisher - Gryphon Books for Writers - who sells it for $19.95. That's much easier on the wallet.