Tao Herb Farm sells not only herbs but also has some really interesting software to help home gardeners plan their landscapes, and some for small landscape and nursery businesses also. Topline Whsle Dist Co - Worms, vermicomposting, worm equipment, worm supplies, worm books and lots of worm information. Now these folks do have a really full site with general information on gardening. This site is new, and just growing, I am sure with time The Garden Net will have even more information, and lots of links. A Chef's Practical Guide to Practically Everything.
Food TV has a fine site with some tasty cactus recipes.
Nopales Rellanos, ummm yummm. This page is from an online magazine that is intended to spread information. I have linked to their page on Opuntia, it has recipes and details on how to prepare the pads and fruit. Please check out Desert USA They also have another page that has some good nutritional characteristics of the nopales, and some fine recipes too. The Holy Land has been experimenting with Nopales for several generations now.