how can i go to guizhou from hong kong by land and where i will be dropped to the city?

If not taking a flight, there is no direct transport mode from hk to GZ, which is a large province. You may reach its capital city, Guiyang.

From the Hung Hom Station, you can take a train to Guangzhou East. Upon arrival, take the subway line 1 to Gongyuanqian Station, where you can transfer to line 2 to South Railway Station.

In the south railway station, there are bullet trains to Guiyang, and the duration is about 5.5 hours.

if i'm from baiyun airport, how do i get to east railway station?
is there any different between guangzhou railway station and railway station?

Well, Guangzhou Railway Station is located at West Huanshi Road, Yuexiu District.
East Railway Station is located at No.1, East Station Road, Tianhe District.

From the airport, you can take subway line 3, get off at East Railway Station. It takes around 35 mins. The ticket fare is CNY 7 per person.

is there any suggestion place we could do camping instead of renting a hostel or hotel?..is there any backpacker hostel in guizhou?..what is the price range for hostel?..i cant afford expensive hotel..

Well, in the downtown area of the city, I’m afraid there is no place for you to camp. There are many backpacker hostels available, here are some for your references.

Huaxi YHA, located at Gaoche Alley, City Wet Land Park.
Backpacker Youth Hostel, located at No. 26 Sichuan Alley, Penshuichi, East Yan’an Road.
Sanrenxing Youth Hostel, located at Zunyi Road.
Suoma Huayuan Youth Hostel, located at No. 54 of Dongshan Road.

Most of them charge CNY50 per night on average.