-Quinoa is a good source of protein for vegetarians, and a tasty alternative to rice/grains.
-You might want to look into making protein shakes (peanut butter, whey or soy powder, nuts, fruit, etc) instead of cereal.
-Of course, good ol' tofu is great for diets. It absorbs pretty much everything you put on it, so it is easy to add to meals like spaghetti bolognese, or put on a salad, etc.
It's a good thing that you do eat eggs already, that should make it much easier to skim out the carbs and replace with more egg/egg white based meals like omelets instead of sandwiches.
You can do it! Good luck!