This place is huge and can be extremely hard to find anything. Simply ask any security for directions and they will happily take you to your destination. Parking is located right in front of the main entrance off of grand central, make sure you park in visitors parking which is the smaller lot. The huge lots surrounding are all for govt employees and I believe you will get ticketed or towed. If you are here as a new hire and need badging done, take the freight elevator down to the basement and follow the yellow footsteps to your destination!