This post will provide a number of hologram resources. There are many of these available on the web, from basic mathematics, to instructions on producing them, to places to purchase supplies. This is just a small sampling.
How holograms are made (some of them, anyway) A nice video from the Discovery Channel
Hologram Kit video Make your own
Of course there's the wikipedia article, which is pretty good in this case:
Intergraf provides a wide range of resources including instructions and kits for making holograms.
Intergraf also maintains a holography news link set here: