Word to the wise though.. Be extreamly careful with wild mushrooms or even mushrooms grown outside in a less than 100% controlled situation. Some mushrooms are highly toxic and can at times appear like edible ones. Eat the wrong one and it will kill you.
Fungi perfecta sells spores/cultures which can be used to innoculate appropriate organic matter, as well as the kits. A much better deal if your serious about mushrooms.
Rattler perhaps you can find some dried mushrooms from an online source?