Don't know of just a list of people with web cams. That detail doesn't seem to be in the Members List since most forums run on software for general use, not specifically for weather fanatics! However, that list does identify members who have web sites. Not nearly as many as I would have thought, so just visiting those might be the easiest way of finding images/videos.
WU also displays web cams that it knows about.
Still, a search for "web cam" + "weather" might get you several thousand results!
How much time do you have?