For a great vegetarian appetizer, try hummus (pureed chickpeas). It makes a great, tasty dip for eating with chips or bread, You can always make it in your blender from chickpeas you've prepared, but you can always purchase hummus mix at the grocery store.
Even if you believe you've chosen vegetarian food in a normal restaurant, be sure to check on how the entrees are cooked -- getting true vegetarian meals in some restaurants can be tricky. For example, vegetables may be cooked in broth, or have tiny bits of meat added to enhance the flavor.