There are many ways to control DC motors from LabVIEW. National Instruments provides plugin motion control boards like the PCI-7342 that are capable of controlling 2 to 8 stepper or servo motor (DC) axes. Additionally you need a drive for power amplification.
You find lots of very good information about controlling motors from LabVIEW with NI motion control hardware under this link:
http://www.ni.com/motion/
The NI motion control boards have lots of high level features like position control, interpolation modes, contouring, onboard programming and so on. Your request is very brief so I can't tell if this level of control is oversized for your application or not. If you simply want to turn a DC motor on or off there will be cheaper methods to accomplish that.
Best regards,
Jochen Klier
National Instruments Germany
