There are a lot of different kinds of stepper motors and they all have different kinds of control functionality. You probably need to research what kind of functionality your computer/system has in terms of communication.
The system I'm working with now communicates via RS232 to the steppers which run on "SmartMotor" commands. This form is really easy to work with in conjunction with LabVIEW if you buy an RS232 card for your PC.
I've also worked with a stepper system in the past that had an arduino driver, so I was sending outputs from LabVIEW through an NI DAQ device to the Ardunio digital and analog inputs. This is NOT the way to do it ideally, but it worked.
Edit: I just saw that this was from 3 weeks ago. I hope it's not too late and you haven't abandoned LabVIEW already.
