sonicstate has put together a series on sampling. Episode 1 is available now and looks at the pioneers of what we today call sampling.
The video is not that in-depth (its only 5mins long) but it does give a pretty good introduction to the area and contains enough info for interested parties to do a little research and get pretty deep.
There is also some useful supporting info on their web page, including a timeline of key developments in sampling.
the other episodes should be worth checking out.
Part 2 - The Digital Revolution is now available
Part 3 - Sampling the Future is now available