who can assist me - how can i go shenzhen from guangzhou by train?

Hi. Ade.
As I know, if you want to take bullet trains from GZ to SZ, you can leave from either GZ South Railway Station or the East Railway Station.

For your hotel, do you refer to the one at No. 2307, Donghuayuan? If so, I suggest you to take a bullet train from GZ East Railway Station to SZ Railway Station at Luohu. Then you can take the SZ Subway Luobao Line to reach Taoyuan Station and then take a taxi to reach your hotel.