If you look at the Thanksgiving recipes on this website (in the USA we almost always have a turkey on our Thanksgiving Day - Christmas can be other meats in place of or in addition to - at our house usually a whole bone-in ham) - it will give you some vegetarian suggestions:
http://vegkitchen.com/recipes-galore.htm
http://www.boutell.com/vegetarian/Thanksgiving .html
http://vegweb.com/thanksgiving/
Thanksgiving "Meat" Loaf
Ingredients (use vegan versions):
substitute for 2 eggs (mix 1 tablespoon arrowroot powder, 1 tablespoon corn starch, and 4 tablespoons water)
1 tablespoon soy sauce
1 box medium firm silken tofu (350 g)
3/4 cup chopped walnuts
1 packet vegan dried onion soup mix (1.5 oz)
1 teaspoon oil
1 1/2 cups chopped onion
2/4 cup chopped celery
2 cups chopped mushrooms (use portobello mushrooms for a heartier taste)
1 1/2 teaspoon each of oregano and basil
1/2 teaspoon sage
1 1/2 cups bread crumbs
Directions:
Mix egg substitute, soy sauce, tofu & onion soup mix together in blender. Add walnuts & blend until smooth. Saute vegetables until onions are transparent (add other diced veggies if you wish - ie peppers, carrotsetc). Add herbs/spices while vegetables are frying. Mix blender ingredients, cooked vegetables and bread crumbs together in a large bowl. Press into a greased loaf pan.
Bake at 350 degress F. for 1 hour and 15 minutes. Let cool slightly. Turn loaf out and slice.