Stock? Built? If so what kind of parts did you have? What kind of kit are you wanting to run? Are you willing to sacrifice some N/A power for a better tune on the juice?

Just to ballpark you....
50hp - High octane, 1 step colder plugs, wet kit
75hp - All of the above + retard the timing and upgraded fuel pump
100hp - High octane, 2 step colder plugs, retard timing, upgraded fuel pump, and check into direct port n2o

THIS IS NOT SPECIFIC TO YOUR CAR!! I HAVE NEVER, PERSONALLY, RAN NITROUS ON A HONDA!!

I'm just trying to give you a baseline. I have put the squeeze on Neons, 240s, Mustangs, Camaros and a few trucks.

You should save the money most people spend on a purge kit and by safety/reliability items first. Nitrous and fuel pressure gauges, bottle heater, fuel pressure safety switch, window switch, and I'm sure there are a few others I'm forgetting.

Somebody will probably jump on this and give you some more specific info for your car. Hope this helps.