Any tips on night photography?

For my newest project (which I'm not going into details about) I will need to start taking photographs at night of buildings and such. I've not had much experience with night photography, and i'm unaware of what aperture and ISO I'm supposed to be working with.

I work with a Nikon D5000, my lens is a normal 18-55 mm (I have a more lenses on order)

Could anyone give me tips and tricks I can use for night photography? Anymore kit I need?

It is okay to take a picture of a black person because it is too dark to see them

I assume you mean lit buildings and that you want to see that glow?

You will need a tripod and a remote shutter release as well.

You need to learn about aperture, ISO and shutter speed and what they do. Just plugging in settings and hoping or accidentally having them work isn't doing you any good. You need to know what you are doing and understand it. You should probably have done that before ordering more lenses. You are probably going to find out the lenses you ordered aren't what you want or need when you finally do know what you are doing or the basics of it.
We can't just tell you what ISO, aperture and shutter speed you need. It is determined by metering the light in the situation you are shooting. What may work on one side of the street or one building probably won't work the same on another street or building.

www.digital-photography-school.com has some awesome tutorials that go from the absolute no knowledge level to advanced.