Michael Nielsen is writing a book on neural nets and deep learning and he's posting chapters to the web. You can access the first chapter here, which uses the recognition of hand-written numerals as its problem domain. You can get access to the rest of the chapters by contributing to his Indigogo campaign.
About Michael Nielsen:
My work is motivated by the creation of tools to help people think better, either individually or in groups. Put another way, I’m interested in cognitive tools and in collective intelligence.
I believe that publicly funded science should be open science, and from 2008-2012 I worked as an advocate for open science. You can get the flavour of my work on open science from my talk at ted.com, or in my op-ed in the Wall Street Journal. I’ve developed these ideas at length in my essay on The Future of Science and in other essays. I’ve also written a book about collective intelligence and open science. It was named one of the best books of 2011 by the Financial Times and by the Boston Globe...