Land Rover Repair: 1999 Land Rover Discovery, land rover discovery, turning the key

Question
My dad bought a 1999 Land Rover Discovery today and at night when he was showing it to a friend the alarm went off and stop we now have the battery unhooked so our neighbors can sleep and we dont have the remote or any kind of manual for the car. We need to know if there is a way to shut off the alarm and immobilizer so that the car can either be returned or taken to a land rover shop to be resynced with a remote.
                                                  Thanks Michael.

Answer
At this point, the alarm is going to go off as soon as you connect the battery.  The only way to clear it will be via the pushbutton on the kay, or by using the key to unlock the vehicle and then turning the key in the ignition.  In some countries the second method (key in door then ignition) does not work.

If you do not have a working remote all you can do is tow the vehicle to a LR dealer or specialist who has a T4 or Autologic to configure a new remote.