Is it possible to get a bus from Changsha to Guilin and can I book it online?

You can take a bus to Guilin from East Bus Station. The bus departs at 16:00, and the fare is CNY 177. You can book the ticket by dialing 86-0731-96228. But I'm afraid that there is only Chinese service. Or, just buy the ticket on the spot upon arrival. Don't worry! :)