My wife is the wild edibles expert of the family and received this book in the mail today from Amazon:
http://www.amazon.com/Edible-Wild-Pl...ds=john+kallas
Here's a couple more that she has and gives high marks to:
http://www.amazon.com/Foragers-Harve...ds=john+kallas
http://www.amazon.com/Natures-Garden...ds=john+kallas