I'll just point you to some sites as I'm not sure how in depth you want to go!
Oh my- I search " plant based proteins" and crazy showed up!
Soy is a great source of protein-and while vast majority of soy is GMO it's what's grown to feed animals raised for their meat. The vast majority of soy, edaname and forms of soy- soy milk,tofu and tempeh- sold for humans is non gmo.
Anyway-searching for vegan protein gets better results for some reason--