I always feel the internet forums are a good way to gain knowledge - asking questions and get some answers from everybody, and SO is a great example. But when I get questions reading some programming books, I wonder to whom can I ask the questions.
O'Reilly and PragProg have their own book forums, and some authors open their own forums. Or, we might be able to send an email to the author if that is absolutely necessary.
Is there any good forum on programming books? Can you share any good programming book forums on the web? Or, is SO the best place to ask some questions in programming books? I found some book reading forums, but not programming books.