it to the computer. A camera can do this if it has audio/video output ability. If it is analog output, it would need to go through a converter like the Dazzle. If it's digital output, you should be able to connect it directly. Software on the computer is then needed to capture the data, and create an av file. Something like Dazzle should come with that software.
You can certainly find a camera on eBay.
I used to build & fly model rockets. One of them was able to carry a small 8mm movie camera. As a result I have a short piece of 8mm movie film with several rocket flights recorded on it. I would like to transfer this to a movie file but have no idea as to how to go about it. Any advice as to equipment needed, etc., would be much appreciated.