So Sagatraders has given the trade list.
This brings the point of WTH is Silverlode thinking when they made the market so poorly. Why not allow big gold trades for units, why limit us?
Why not build a better search engine.
Anyway, as a sample, here is the undead list. Overall its a pretty good list.

If you can get to Level 35 you can farm a TON of gold. Good way to play for free imo. Get to 35 then start collecting your army.