"The Art and Skill of Radio-Telegraphy"
http://www.raes.ab.ca/ -> cw book -> Free download versions in PDF
Have you read this book? It's freely available and I found it very (very) useful. Written in English but also German translation available.
YES everything is for free under ONE simple restriction, and that is that you download it from the original website.
There you can read:
Official Download Site
"You may link to this page, but please do not put the book file on your server."