In the past, there were quite a few flights a week between Wuhan and Huangshan. Unfortunately, they were cancelled in the first half of 2004 due to SARS, and we are not sure when they will be resumed.
There is no direct train from Wuhan to Huangshan, and you need to change to another train before getting to Huangshan. The connection, however, is no good and you'll have to wait at least 4 hours for the proper train to come.
So, at present, bus is the the most convenient means of transportation from Wuhan to Huangshan. It takes you about 10 hours to reach Huangshan Mountain (not Huangshan City, which is an hour apart) by sleeper bus.
There are 2 buses everyday leaving Wuhan Xinhua Road Long Distance Bus Station (located at No. 1329 Jiefang Avenue, Hankou) for Huangshan at 08:30 (seater bus) and 17:30 (sleeper bus). If you take the latter bus, you will be staying overnight in the bus. Both buses make a stop in Tunxi before driving finally to Tangkou, a village near Huangshan Mountain. The seater bus costs RMB220 while the sleeper bus costs RMB238. Inquiry of Xinhua Road Long Distance Bus Station: 027-857777988.
You can also take ship to get to Guichi or Anqing from Wuhan before changing the bus to get to Huangshan Mountain. Considering that the cable car stops operation after 16:00, you may have to stay at the foothill or in Tunxi for the first night.