The Beastiary - A expensive purchase but also a must have. It is the Bible of the Narrator. Not to have one would be unthinkable.
A Saga Companion - A fairly new release that isn't needed. It basicly tells about spellbooks, skills, and elaborates on histories. Mainly for the players that have a hard time coming up with original ideas for their characters.
Tower of High Socery (Box Set) - Not truely needed for a creative narrator. It does give a large assortment of magical items and their attributes but names are very generic and have very little thought put into them. E-mail me if you want to know more about this set and I'll gladly send you a summary or post it on the page.
Palanthas - A new supplement I have yet to sit down and review. It will come in the future.
Honor's Face
Honor's Face can be willed, in the most dire of cirumstances, into a blazing dragonlance with the attack power of +80.