I'm getting a $500 alarm installed today. It's from an auto electronics tech and he's doing it for $250. Viper alarm.

EDIT: Installed! It is awesome! remote start and all! It has the hook up for trunk pop when I get a solenoid for it. I love this alarm. If you're considering it, get a nice DEI alarm. Viper, Clifford, Hornet, they're all the same, but Viper has the most features I believe. It is so much better having keyless entry.