A serendipitous turn of events led me to the software (LabVIEW) that I have been making a living from for the last 9 years. And I learned it from a book first. Since then I have had formal training, a little bit of mentoring, but many more books. Code Complete is one of the best and my favorite. Although it teaches little about my actual software, what I have learned from it about software engineering principles and project management gives me a much deeper appreciation for the big picture and how to get a project done most efficiently.