get a viper system from ebay and have a shop install it, im not sure the models but dont go cheap or you might run into some serious problems.
For instance, I have an AutoPage 2way remote start, sometimes it wont start and sometimes it does (with the remote). Recently it started making my car actuall not start when i use the key, it just doesnt turn over at all. This can be a real pain if your a long away from home and your car wont turn over.