Michael Tierno Aristotle's Poetics for Screenwriters (Hyperion 2002) [or if you'd like the real thing: Aristotle, Poetics]

The Digital Storytelling Cookbook (Joe Lambert, Center for Digital Storytelling, February 2007)

Various PDF's and readings (see weekly listings)

Strongly Suggested (Will serve you well in the future):
Carolyn Handler Miller, Digital Storytelling: A Creator's Guide to Interactive Entertainment (Focal Press 2008)

Garr Reynolds,
Presentation Zen: Simple Ideas on Presentation Design and Delivery (New Riders 2008)

Good to Have
Joseph Campbell, The Power of Myth (Anchor, 1991) [Chapters 3-5]

Joseph Campbell,
The Hero with a Thousand Faces (New World Library 2008)

Jane Stevens, Knight Digital Media Center,
A Story from Start to Finish