You could get an alarm with all the bells and whistles, but it will only keep honest people honest. That said, viper and clifford are two of the more popular and widely used, they are also the more expensive ones. I got one by the Cobra company, and it works pretty well, only gripes are the shock sensors are too sensitive andthe remote start sometimes has to try 3times before starting.
Good Luck with your search, and Welmoe to the Org.
-BG06.