Visual Basic and Grasshopper

Hi, 

I am pretty new in using VB in Grasshopper. I have some very basic questions from the scratch!!!: 

For example why when I am using the constructor (Dim new_point as New On3dPoint) to instantiate  a new point from On3dPoint class, after typing "New" I can not see a list of all classes to choose from that list? and even after typing on3dpoint, the VB does't recognize that class?

Does anyone know some good examples of using VB in Grasshopper? I just found some in "The Grasshopper Primer-Second Edition", anything else?  

Thanks a lot for your help

Nick