bullet train

I love to visit China. I'd like to travel from Guangzhou to Changsa by bullet train. But i understand that there is more than 1 train station. which one should i take?
AND which is the best budget hotel i can stay near to this train station as my arrival at Guangzhou is about midnight. So i'd like to go to Changsa early next morning. (can furnish me the departure time of the train?)
Thank you very much....