Mod Making Help
Major Pain's How To
This tutorial not only shows the basics of handling files within the game structure, it also explains how to skin a unit and set the paramaters for the unit's xml file.
Tangram's Building Modding Tutorial
Basic guide for the creation of buildings.
kaoz' Building Tutorial
QuickGuide on building houses in 4 steps. One of those steps goes deeper in how to set the parameters for the building in the ResEditor.
kaoz' Acks Tutorial
QuickGuide on how to add sound acks to your units.