How private are web cam transmissions? Is it easy to intercept a transmission? What happens to a transmission once it is sent? Where does it go? If a web cam transmission isn’t immediately recorded, can it be somehow found later? Do the cameras themselves record the transmission or just send it?
Obviously, I’ve made some poor choices, and I want to cover my tracks. Please help!
What research have you done so far? Any hits on google?
You mean like a Quickcam? They don’t store the image, just send it down the wire to your computer. There could be a cache of the cam’s images on your computer. It depends on the software.
As to how private are the transmissions. It depends on what method you used to stream the images. Was it on a web site, Yahoo, or what? For most, they aren’t very private. Anyone can connect to (like with a web site) and see them and nothing stops someone from saving the images.
As you can see without more info there’s no way anyone can give you a better answer.
If you are talking of something like NetMeeting then anyone could have intercepted the transmission but, in fact, the odds are minimal and I would not worry. The only person who could have saved it is the person at the other end so the question is a matter of how much you trust that person.
BlakeSintek -
nothing to add but WELCOME to SDMB!
I think in order for us to help you, you’ll need to describe the video you made, slowly and in great detail. 
It was on yahoo messenger with a logitech web cam. So where does the transmission go once it is sent. Is it floating off into space?
The route of the pictures go from:
For 1, the camera has very, very little memory, it sends what it sees straight to the PC. It’s not a security concern in the least. (Well, on its own.)
At step 2, the bulk of the pictures are stored only momentarily. Some, esp. the last frames, might still be hangin around on your harddrive. Tucked away in the swap file, in temp files, in unreclaimed clusters, etc. Empty your temp directory and then do a defrag will make most of those go away. Only a determined person would be able to recover a little bit after that.
At step 3, any Evil Person admining a router along the route from PC to PC might be sniffing for such images and automatically storing them away. The percentage of such Evil People is presumably small, but given the huge size of the 'Net, it still comes out to a good number.
At step 4, the receiver can do anything he/she wants with the pictures. Save them, broadcast them out to others. Burn them to VCDs and sell them out of Malaysia. Etc. That is the big vulnerability.
Note that things sent over the 'Net are sort of like postcards. A bad mailperson can read them, copy them. But keep in mind, that there are trillions of “postcards” flowing around the 'Net every day. The chances of someone peeking at yours is small, unless it’s interesting. Like a web cam. The person at the other end can do what they like with it.