It's a 300ZX, not a Fairlady.
License plate light:
http://www.thezstore.com/page/...-1194Although I think I still have one in really nice shape. Let me know if you're interested.
Lighting problem. Typically, this is the headlight switch mounted on the steering column. Replace it.
Windows: Check fuses.
Button on the top right: Rear defogger button?
Button next to shift knob: Do you have an automatic?
AC vents: Replace vacuum lines. Start with the ones under the hood. Generally fixes most of the Z31s out there with climate control issues.