If you are looking for a lower stance, but with good ride quality you need springs that are prgressive rate like the Eibach Pro-Kit. It lowers the car 1.5 in., and you can get away without caster/camber plates, but they wouldn't hurt.
If you are going simply for looks and performance, and don't care about ride quality, then something like the Eibach Sportlines, which lowers 2 in., would be the way to go. These are specific rate springs BTW.
This is the main question you need to ask your self in my opinion...