I was actually looking for some videos when I chanced upon this site called TV Eyes. This is a search engine for all things TV and video. Just to test out how it works, I typed in "Bon Jovi" in the search bar and I was surprised that it returned a page full of results which made up of Bon Jovi's appearance on TV, interviews and other shows. This is just like Google, but it searches exclusively on TV and radio sources and the results were pretty exhaustive and spot on too.

I would like to mention that TVEyes is a commercial site but they do have a basic search which is free. People who require more in depth searches would have to pay for a subscription to TVEyes Professional.

If your work involves a lot of searching for TV or radio clips, this is a good source for you. It's pretty fast as well and most of all, it is free!