I just finished a small article on stoneware crocks, and some of the source material proved quite interesting. Here, perhaps is all you ever want to know about the fine art of the stoneware crock and it's use in food preservation.
http://www.makesauerkraut.com/fermentation-crocks/You can buy stoneware crocks and kits here
http://www.pressurecooker-outlet.com/Fe ... Crocks.htm