Hi. Ask, and ye shall receive.
One thing that can get you off to a good start is proper documentation. The links in my sig lead to threads where the Dom3 DB files have been posted. The DB is a series of spreadsheets that contains the stats of all units, magic sites, weapons, armor, independent population types and forts in the game. Magic item list is under construction but on a backburner right now.
You're going to need Open Office to read the DB docs, but they should come in quite handy for you.
The other resources you're going to need is the
Spell Modding Guide by DrPraetorius. I'm not at all familiar with spell modding and the effets, but afaik that's the most comprehensive documentation available on the subject. There are some sprite number lists and other related stuff available elsewhere here, but right now it's 1:35 am here and I need to go to bed. I can look them up later.