Hey troutfisher,
One alternative is to use Google image search. Type in the binomial (Latin name) and you'll get more colour pictures than you can shake a stick at. I would caution, however, have a book nearby to compare with because sometimes the plant picture that comes up is not the plant it's labelled.
Generally speaking, edible plant books do not give you good pictures or descriptions. You must couple them with good ID field books. One exception is Edible Wild Plants- A North American Field Guide, Thomas S. Elias/ Peter A. Dykeman, Sterling Publishing (Outdoor Life), 1990, ISBN# 0-8069-7488-5. I don't know if this is still available, maybe a used book store?
One other thing, I would suggest you don't rely on one edible plant book, even as good as the Peterson series is. With more than one book, you can cross reference the plant to see if there are any surprises. For example, I have one book that says the berries of Virginia Creeper (Parthenocissus quinquefolia - sp?) are edible and others, that say they're poisonous.
So if you're going to learn from books, have several. Also a couple of books on poisonous plants is a good idea to make you aware of poisonous look alikes, and most of all, be meticulous in your identification, especially when learning. Many years ago I almost let my daughter (and myself) chow down on some Canada Moonseed (Menispermum canadense) which is a poisonous plant, because of a too casual ID (mistook it for Wild Grapes [Vitis spp.])
Happy foraging!
Doc