Hey hardwired,
It depends on what version of measurement studio you are using. If you have 6.0 you should be able to find the help file by going to Start-> Programs-> National Instruments->Measurement Studio-> Help-> Measurement Studio Reference. Then just go to Contents, pick VB or VC, then reference and finally pick VISA Control.
If you are using MS 7.0 with .NET then the help is integrated into .NET. In .NET go to Help-> Contents-> NI MS Help-> NI MS .NET Class Library ->Reference ->NationalInstruments.VisaNS.
I hope this helps out.
JoshuaP
National Instruments