Put the dried mushrooms in a bowl, and cover them with hot water. Let them sit for 20 minutes, then drain.
Cut the ends off of the lotus root, and peel the skin. Slice the lotus root into ⅛- to ¼-inch pieces, then put it in a bowl of water with the vinegar for about 20 minutes.
Cut the carrots into ½-inch slices, and slice the celery on the diagonal. Peel the ginger, and cut into slices. Cut each mini corn into 3 pieces.
After soaking, bring a large pot of water to a boil, and drop in the drained lotus root and carrots. Cook for 5 minutes, then drain.
In a small bowl, combine the oyster sauce, soy sauce, sugar, salt, pepper, arrowroot powder, and water.
Add the oil to a large frying pan and heat to medium high. Add the ginger and stir for 1 minute. Add the drained mushrooms and stir fry for 2 minutes. Now add the lotus root, carrot, celery, baby corn, and ginkgo nuts. Stir for 1 minute, then pour in the sauce. Cook for 1 more minute and serve.