As far as using Qt classes, there is great documentation that comes with the Qt developer tools. If you have kdevelop installed then you should be able to run assistant from the command line. I first started doing Qt programming using Programming with Qt, the O'Reilly book. It wasn't bad, but certainly assumes you know C++ well before you start so if you don't you probably want to start with something else.
As far as a book on how to use kdevelop, I haven't seen any personally, but that certainly doesn't mean there isn't one, I would check amazon.com or something.