This depends on a couple things. Budget and options.
If you want to be able to adjust your ride height you need to look at coilovers, but they're costly. If you want a cheaper setup, go with some good quality lowering springs and aftermarket shocks. You'll need to upgrade the shocks once you lower the car because they'll blow.
I'm on the Eibach Pro-Kit which is only a 1.3" drop and I have Tokico Non-adjustable stocks. The Eibach springs are stiff and not bouncy at all. I'd recomend the Eibach Sportline springs (1.7 - 1.9" drop) and they're under $200. You can get the tokicos for a little over $200. That would be a great setup.