If you can tolerate them... beans, nuts, eggs, whole grains, dairy are all good sources of protein.
I know a lot of people have trouble with whole beans... but you might want to try tofu or other fermented soy products.
Same with dairy -- many people who are lactose-intolerant are able to consume cultured or fermented dairy products like yogurt and kefir, where much of the lactose is converted during fermentation.
And if grains like wheat are a problem, you might want to try quinoa or steel-cut oats.
Again, it all depends on what you personally can tolerate, but there are lots of meatless sources of protein!