If yours is like ours, the program/disarm switch is under the dash; a push-button type. Ours is just dangling at the end of the wires to which it is connected. The control box is nearby, close to the steering column but still in the dash area.
If you don't have a key fob transmitter I'm not sure how you would go about arming/disarming the alarm. However, it is probably a Crimestopper brand alarm for which documentation exists on their website Crimestopper
or you can call them at 800-998-6880.