So you want to get more people to buy the Sovereign Press Dragonlance d20 setting books....
A few suggestions-
A) Have a race war in which the objective of the modules in the campaign is to exterminate every Kender, Gully Dwarf, and Tinker Gnome in the game. This will work as incentive for all of those who hate those races, to buy your new books. It will also be unique in that it will be one of the first deliberately genocidal campaigns ever made. (No, I'm not being an ass here, there is a lot of dislike for the above mentioned races - an extermination campaign would get those haters on your side, or at least their money in your pocket).
B) Declare a discount on all the already created Dragonlance material, this will get any current product moving and get it into circulation where more of a player/customer base can be built. If there is any product, I don't know, I don't see a lot of it in game stores.
C) Destroy Krynn as we know it. Advance history about 10,000 years and rewrite the entire setting as something similar to WotC's Urban Arcana for the d20 Modern system with appendixes for conversion to both d20 Past and d20 Future. The struggle for Krynn will still be ungoing, but will be fought in new eras.
These are all pretty radical suggestions, but then again, that's the point of this thread.