You will also need to collect some (free) software to capture the data. I currently use KC3tools which you can get
http://pk3.org/Astro/
You also need to get software to stack the images such as registax. Oh and a good laptop with lots of memory recommend 1gig.
Webcams can be modified to take long exposures and I understand the modification works out cheaper then the commercially available meade dsi etc. You then have a camera for both deep sky and planetary. But there is a very steep learning curve!!