Some good examples of online resources that aid in mushroom identification are UrbanMushrooms.com and AmericanMushrooms.com, both of which feature sizable galleries of photos and information. Another helpful website is MycoKey.com, which offers an identifier tool developed by two Danish experts in mycology, the scientific study of fungi.
There are wide selections of printed field guides available from some book retailers designed to educate the layman in mushroom identification. These commonly emphasize mushroom varieties considered edible and may contain information on how to gather, prepare and cook mushrooms in addition to photographs and basic information on the various species. However, there are many poisonous mushrooms that are similar in appearance to the edible kind.