Hi wellcome to china spacially wellcome to Urumqi,
if you want to buy cloths ,zhanxi road cloths market and some other markets at zhanqian road. all of them located around the Guangzhou railway station. if you want to buy from Urumqi,changjiang road cloths whole sale or zhong shan road cloth whole sale market is better.
from guangzhou to Urumqi have no diract train.so you have to stop ower lanzhou.you take a train t264 or t265 to lanzhou,it takes about 26 hours.then, you can take train from lanzhou to Urumqi ,has many train to Urumqi in lanzhou takes about 20 hours.
i think you take a flight is better,if you buy flightticket befor one week,you can get discount.have a nice trip

I am most greatful for your response Mr. Osman. Many thanks.