A lot of MFC's have an analog out denoting the "is" value of the mass flow.
Connecting this analog out (from the MFC) to an analog in of a DAQ card will allow you to record the values.
This is an easy thing to do (If your MFC has a simple analog out), so I'm not sure if you'll find ready-made functions for it.
Shane.
Using LV 6.1 and 8.2.1 on W2k (SP4) and WXP (SP2)