I've never tried anything like this, but I can tell you that DirectX is a Microsoft COM object that is designed to give developers access to video and sound hardware without resorting to hardware specific drivers. Since it is a COM object, you should be able to access the DirectX classes from labview using ActiveX programming. In another discussion on the same topic, Ian Nelson suggested some Microsoft links where you could go for more info about DirectX and Joysticks.
http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RNAME=ViewQuestion&HOID=5065000000080000009E0E0000&ECategory=LabVIEW.LabVIEW+General
