coilovers are the way to go! (NOT Ebay ones as mentioned several times above)
It really all depends on how stiff and low you want your ride to be, my old eg9 (no one knows about hahaha!! wasn't on the site at the time) had just aftermarket struts and springs. It was riding on tein springs + Tokico Illumina struts. Gave the car about a 1.5" drop and was surprisingly quite comfortable.
If you want something that is cheap and comfortable, (dont want to spend so much on coilovers) for Daily Driving and should last, I can suggest some Tokico Blue HP struts (around $300 shipped I think) and some Tein S-Tech springs. That will give you a 1.5" drop, comfort and its quite affordable for the quality parts you are buying. This set up will cost around $500?
Or buy some good coilovers for $800-1000 and adjust the height whatever way you want!
This was my old set-up:
