I worked for two years as a senior technical trainer for Sencha. Below are some links to pages that should be useful for programmers using Sencha Touch 2.
Sencha Touch Outline
This is extensive outline of what we taught in our Sencha Touch course. Download a doc version here.
ExtSpect is a Touch 2 plugin that allows you to inspect the internal components Touch 2 apps. (On GitHub, click on the [ZIP] button to download.)