The bus fare from Guangyuan to Jiuzhaigou is about 80-90RMB and I think it is the same from Jiuzhaigou to Guangyuan. I have no idea about the time. There is very few buses between Jiuzhaigou and Guangyuan. More people will choose Chengdu for the bus and road condition are better. Buy train ticket to where?! No train to Jiuzhaigou, only bus and flight.

Thank you Ms Dora for your info, I was referring to taking a train from Guanyuan to Xian by sleeper train, can I get the train ticket when i arrived Guanyuan in the afternoon?
Thxs