The best way from Hong Kong to Guangzhou, by train, from hung Homg train Station to Guangzhou East Railway Station, within 2 hours and ticket fare 190HKD. Advantages: faster (short time in pass the border custom)
As to the hotel, ti is a clean 4-star hotel, but not very well located I think. It is not far away from Guangzhou railway stations, but not very close to, and without walking distance from the main business streets. While the hotel has shuttle buses (herpahs free) to Garden Hotel, where you can catch airport bus, Guangzhou East Railway Station where you can get Hong Kong by train, Tianhe City Plaza where you can go shopping. If you want to go Shunde and Shenzhen, you can get to Tianhe bus Station.

Currently, both of the train and bus could be used for traveling from Hong Kong and Guangzhou directly. You could choose one as you like.

It is suggested that you take the train to arrive at Guangzhou East Railway Station, then you could hire a cab to drive you to the nearby Euro Asia Hotel with a fare of CNY15.

This hotel has good location, and a good choice for the Canton Fair. As I know, it supplies free shuttle bus to the exhibition center.

At the Guangzhou East Railway Station, you could catch one of the frequent bullet trains to arrrive in Shenzhen in 70 minutes, very easy~

Thank u Mr. Andrew and Mr. Frank for your replies. Very informative. :)