Cadillac Deville Theft System Problem Please Help!?

[Sara]

I have a 1996 Cadillac Deville and for a few months, even maybe a year or two the car has said theft system problem car may not restart but i have always got it started. Yesterday however I parked it in the driveway and when I went to leave I could not get the car to start I have tried all my spare keys and the battery and engine are fine but when I turn the key I hear a sound kind of like when the doors lock it's like something moving but comes from the dash or steering column and is kind of like a grunt sound. Then I get the message starting disabled due to theft system remove key from ignition. Are there any quick fixes or do it your self's for this before I have to have it towed to a mechanic. Thank you for any help