Hi Michael,
what you should do first is to make sure you have your software sources download location set to “Main” and that you also have “Canonical” marked, see the update guide (see below for link) about that!:
Now install the following via a terminal (Ctrl + Alt + t) (even if you don’t use Skype or the other packages are installed):
sudo apt-get update && sudo apt-get install ubuntu-restricted-extras skype libv4l-0 cheese
Then test your webcam with “Cheese”. 