There are several foods that can be eaten that contain a very high nutritive value and provide ample protein. Spirulina, a cyanobacteria, is very good as are chlorella, barley grass, wheat grass, and other plant sources.
Wheat Roast, which is marinated, cooked gluten is a very tasty substitute for the soy products, while the "super greens" are used as supplements.
Before using these herbs, algaes, and the likes...CONSULT YOUR PHYSICIAN!, and inquire about possible inter actions with medication, allergies, etc.
Whole Foods market carries many alternative protein sources and their employees are extremely knowledgeable, and aim to help out as much as possible with your diet, but keep in mind that, while being knowledgeable, THY ARE NOT M.D.'s!
If you have specific allergies or require a speecial diet because of a medical condition, I would advise you to seek the help of a ADA Registered Dietitian.