There are two mushrooms that come to mind for me. The first is the Fly Agaric (Amanita Muscaria) this is that pretty one with the red cap and white spots that show up in fantasy art occasionally. It is also featured on the Shaman card in the 'Sacred Circle' tarot deck. The other is the Psilocybe or so called Magic Mushroom both of these have been strongly associated with both shamanistic and magickal practice in the Old World and New, partly because of their hallucinagenic properties. Now, don't get me wrong I'm not promoting drug use here. You should certainly Not EAT THEM. The Fly Agaric is strongly toxic and deaths have been known to occur. In addition the possesion of Psilocybe is illegal in most all of the US. It is because of these properties that I feel they would be strongly associated with the Moon. There is one other I might recommend and it certainly is dangerously toxic. This one is called the Jack O' Lantern (Clytocibe illudins) because it has the unusual characteristic of producing its own illumination-very pretty on a still dark night. You won't be able to buy any of these though. Note: You should get a good feild guide as you'll certainly have to gather all of these in the wild. Happy hunting.