Ext 2 Overview
This is where I read about component model and component life cycle, and how to extend different classes in Ext JS.
Creating new UI controls in Ext JS
This document written by Nigel White aka Animal describes how to create custom user interface controls by extending the capabilities of existing classes in the Ext JS library version 2.0 and above.
Nice set of articles by Jozef Sakalos:
Writing a Big Application in Ext (Part 1)
Writing a Big Application in Ext (Part 2)
Writing a Big Application in Ext (Part 3)
He has nice examples and file patterns too, check them out.
