There have been many threads which discuss this. I should dig up some of the better ones and post the links. Maybe later if there is interest.
Some tips:
If you turn on logging (the -dd switch) you will get a text log with everything the game is thinking. How it rates your actions, decides results, adds things to the game, AND the thinking of the AI. To record that for even ONE turn is a really really big file. For example: for a recent discussion on how to improve AI casting I pulled out one small bit of a log. This is the AI thinking about ONE mage namedZrakhnadar in ONE round of ONE combat to cast ONE spell.
http://www.dom3minions.com/files/spell_ai.txt
Also if you play a game with computer players and turn on computer turns (the hidden switch of --comptrn ) then the game will save .trn files for the computer players which you can pick up and view