This is a quick post (see the longer post on my personal blog: Open Sourcing “The Screencasting Handbook”).
I have just open sourced this eBook as a free book (it has been commercial for 3 years) as some of the content (mainly relating to software packages) is looking a little old now. The techniques and processes still look very sensible.
The new license is noted on the homepage along with the download link. Please note the requirement for attribution back to this site and to me if you use or discuss the book.
To improve your screencasting knowledge you must read The Screencasting Handbook. The author (Ian Ozsvald) also blogs.