There is no direct bus from Hangzhou Airport to Nantong. You have to stay one night in downtown area. Upon arrival, go to take shuttle bus to its terminal at Wulinmen in downtown Hangzhou. On the next morning, you should take a cab to Hangzhou North Bus Station and then catch a coach to Nantong. It will take you about 5 hours.

Thank you for the nice courtesy and kind reply

I was thinking of taking Bus from Hangzhou Airport to Shanghai Huangpu Bus Station and from there to Nantong.Can you please help me out with the following
1) Is there buses available from Shanghai Huangpu Bus Station to Nantong , time taken and fare idea
2) Best area to stay in Hangzhou ( easy access to all main places , active night life , Indian Restaurants , etc...), suggest me economy hotel if possible

Thanks