Night photography is not as difficult as you might think. Firstly, and most obviously, you will need a sturdy tripod and a remote shutter release cable (or wireless remote shutter release).
Take test shots: Below are a few tips, but the best thing to do is to take a series of test shots to determine the settings that will best suit the situation you are shooting in.
For best results head out of the cities and big towns and find a place where there is little or no light pollution. And also shoot on a new moon night, or when the moon has not yet risen. You can get good results on moonlit nights too, but ensure it's not a full moon, or shoot when the moon only just beginning to rise. You can get blues in your sky on moonlit nights, so it's not always unwanted.
ISO - Set your ISO to around 1000 - 1600, depending on how bright the sky is (when there is a moon the sky will be a little brighter). If your camera's ISO goes higher by all means use it, but remember the higher the ISO, the higher the noise. This is especially true in darker images. So try to attain the lowest you can to minimise the risk of noise.
Aperture - I usually go for an aperture of around F5.6 - F7.1.
Shutter speed - Try to attain a shutter speed between 10 - 30 secs.
Focussing - Focus your camera to infinity, or just below if you have foreground interest.