Hello W,
If you go to the vision forums and search for "USB Webcam" there are a number of posts with links and information about drivers and image acquisition in LabVIEW. Below is a link to the vision forums:
http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=8&RFORMNUMBER=3&RHIDETAG=TRUE&UCATEGORY_0=_15&UCATEGORY_S=0
I hope this helps,
Sean C.
Applications Engineer
National Instruments