I recently discovered how to change the game (with MCP) and now I'd like to do my first "big" change to the game, creating new mobs. I already made their skin, the model, the AI and added a new entityID to the mob list. I just need to know how to make them spawn normally under similar conditions to zombies and skeletons.

Thanks in advance! :D

EDIT: Also, if anyone knows it, post tutorials about minecraft code editing, that would be great.