The GM862-GPS is probably proprietary device and I rather doubt you ar going to find much in the way of models for simulation. What you are going to have to do is create these yourself. You won't be able to simulate them, but you can create dummy parts with no models for schematic entry and pcb layout purposes. You will also have to create Ultiboard footprints also and there is a tutorial on how to accomplish this on NI's website (I don't know the exact URL)
