For night shots, you don't need any filters or special lenses. In fact, filters can sometimes give unwanted reflections, so you're usually better without.
The keys to nicely exposed night shots, assuming you are willing to take the time to set up the shot and not looking for hand-held candid style shots, are:
Tripod - or at least a level surface to put the camera down on.
Self-timer - or remote release - anything that lets the camera snap the shutter without your hands on it.
Low ISO - set your camera to the lowest ISO setting available, be it 80, 100, or 125.
Longer shutter speeds - things that are moving will blur or streak, but things standing still will come out sharp, detailed, and nicely lit, with that crisp night shot look most people like. Longer shutter times will give you great colors and bright, vibrant lighting, while shorter shutters will retain more of the dark composure for more realistic dark-sky appearances...how long you choose is based on what you want to achieve.
Manual mode is usually best, once you get to know how to set shutter speed and aperture for the right effect. But until you master that, you can use the Night Scene mode (usually looks like a moon icon), or you can use Shutter Priority mode and set the shutter to 5 seconds or so...check the results and if you want it brighter, go longer on the shutter, or darker, go shorter.