The neutral safety switch on a 1996 Pontiac Grand Am is located on the
transmission. It's usually on the side of the transmission, near where the shift linkage connects. However, the exact location can vary slightly depending on the specific transmission type (automatic). You'll likely need to get underneath the car to see it clearly. It's a relatively small switch, often with wires connected to it.
Because accessing it requires working under the vehicle, exercising caution is vital. Make sure the car is securely supported on jack stands, not just a jack. Disconnect the battery's negative terminal before starting any work near electrical components. If you are not comfortable working under your car, it's best to have a qualified mechanic perform this task.