While appetizers are typically enjoyed before the main meal is served, there is no reason why you can't create a filling and enjoyable meal by foregoing the main menu and ordering off the appetizer menu. At any good Italian restaurant, it should be easy to find a variety of vegetarian appetizer options on the menu.
Most of those vegetarian options can easily be made vegan by eliminating cheese from the dish. For instance, fresh tomato platters that come with cheese usually also come with delicious toppings such as olive oil, fresh basil, olives, and balsamic vinegar.
Just ask the server to omit the cheese, and you've got yourself a vegan dish! Keep your eye out for appetizers that feature mushrooms, eggplant, or peppers in them, as you can usually order them vegan without confusing your server.