The camera is a really important part of the project because it will document the trip to near space. Many people opt for the GoPro 2 HD video camera which is especially made to handle harsh conditions and hard falls, but since I don't have that much money to spend I brought a regular off the shelf camera from Canon.
This is a 10 MP camera which you can easily order from Amazon.com. But how will it take pictures by itself? That's where CHDK comes in. CHDK stands for Canon Hack Development Kit. It won't hurt your camera (don't trust me).
There's some great tutorials online about how to get CHDK up and running. You must order an SD card that is greater than 4GB in order to get as many pictures as possible. You will want to run the intervalometer for at least 10 second intervals. This will give you about 2000 photos of the flight. Now, I will remind you that this are photos. If you want a video, I would recommend getting the GoPro.