There is virtually no reason to miss out on essential nutrients, especially protein sources, just because you are a vegetarian. The growing popularity of vegetarianism had resulted in abundance of soy and grain based substitutes for most of the common animal products.
Most of these substitutes are easily obtainable from your nearest typical supermarkets and grocery stores.
Check out the chart below and head on to my other blog for complete details. It even has links to tasty recipes that you can use to prepare your meals. They're yummy, I assure you.