i just discovered, and blitz-read through the online version of Learn Python, the Hard Way.
it’s, as of now, my favourite Python instruction book (and it’s near the top of my list of books to learn practical programming from).
the entire book is online, for free, in HTML format, but i think it’s part of a more complete course package. it looks to me like the authors charge money for access to pdfs and related video tutorials (though you don’t have to pay the price they request if you don’t think it’s worth it – i found a “name your price” type of agreement for the videos over at inculcate.me )
UPDATE: apparently, a hard copy of this book is available for preorder on amazon