Here's a picture I took from my front garden. It's a composite of 82 pictures, each of around 15 seconds exposure. All I did was mount my Canon Powershot A510 on a tripod, set fixed exposure of 15 seconds, point it at the sky and take shots in continuous mode, with an elastic band holding down the "shoot" button.
The images were aligned using hugin and averaged/normalised using a little program written for the purpose. The Andromeda galaxy, M31, is clearly visible in this shot. I've marked Cassiopeia and put a ring around Andromeda.