This site that will tell you more about natural farming in general and the approach they advocate to raise pigs and create deep pen floors. This page on pigs contains video's, guides, and an in-depth online course of basic swine training. Worth checking out!
This site has a wealth of information on how to farm in a small scale way using local resources and wisdom. It looks at what appropriate technology, sustainable energy, sustainable farming, family nutrition and local self-reliance can be used to enable people to live off the land. Take a look. There's lots to inspire and get you thinking about for your own operation.
European Commission website that is responsible for farm animal welfare standards across Europe. Their range of authorative reports into the pig industry by their standing veterinary committee make clear just how desperately higher pig animal welfare is needed.