I am familiar with the basics and fundamentals of C++ and now I would like to move on to designing and coding GUI features of it, interactive dialogues, etc... like VB or Delphi
Where do I start (self teaching text book, online tutorial)?
Here's how I prefer to learn how to program a new GUI system:
I'm not aware of any good books that cover more than one GUI platform well, and that's probably not feasible on at an introductory level.
For GUI features like VB or Deplhi, yeah, Bob Murphy is correct, you're going to have to choose a platform and then go research it. A book is a good idea, but you can also make headway using online tutorials.
As an alternative, if you want to experience full graphical control, try out a graphics library like SDL or openGL. Both of which have libraries that provide the typical GUI constructs like textboxes, buttons, checkboxes, radio buttons, etc.