The new ModWorks forums at SE.net will be dedicated to all aspects of modding Space Empires IV, from data files to making effective AIs.
There's nothing there yet, but the goal of ModWorks is to develop an extensive repertoire of modding tricks and techniques, while building a helpful FAQ and encouraging discussion of new ideas.
Feel free to drop by and post questions or tips you might have.
You can find the ModWorks forums here:
ModWorks Forums