National Instruments produces lots of software, if you could be a bit more specific you will get a much more concise response.
Try here for starters: -
http://www.ni.com/support/
For hardware drivers (e.g., NI-DAQ, NI-488.2,
NI-IMAQ, etc.), firmware updates, or application software updates
(e.g., LabVIEW, Measurement Studio),
http://digital.ni.com/softlib.nsf/MainPage?ReadForm&node=132010_US
Hope this helps