there is a bunch you can get. dropzone (2in), sprint (2in), B&G (1.6), Eibach (1.5/1.3), H&R (1.3), and others which i dont know about which include apexi and maxspeed.
I just bought the B&G springs because they ride really comfy and have a 1.6 drop. i also have 17's. If you want a lower drop go with either dropzone or sprint. you will sacrifice the ride quality tho...
once you lower your car, the only other mod u NEED to do is get new struts/shocks. mos def go with the kyb agx or the koni inserts.