Heat oven to 400° F. Place garlic bulb in small microwave-safe bowl; cover with microwave-safe waxed paper. Microwave on HIGH for 1 to 2 minutes or until very soft. Break garlic cloves apart; set aside to cool slightly.
Press garlic cloves lightly to squeeze out soft garlic into small bowl; mash with fork. Add sour cream; mix well. Gently stir in feta cheese.
Grease 12-inch pizza pan. Unroll dough; place dough in greased pan. Starting at center, press out dough to edges of pan. Bake 10 to 12 minutes or until crust begins to brown.
Meanwhile, heat oil in medium nonstick skillet over high heat until hot. Add onion; cook and stir until onion begins to brown, adding 1 tablespoon water if necessary to prevent scorching. Spread crust with garlic mixture. Top with artichokes, onion and shredded cheeses. Bake an additional 10 to 12 minutes or until cheese is melted and crust is golden brown.