They had some really pretty ones in Shenzhen, with matching beach bags. I know, not that close. We normally use our leftover plastic tablecloths from birthdays.
If you are going to a beach, they will have it in the shops near the beaches.
I've also seen them from time to time in Justco $10 stores and JapanHome stores.
I forgot to mention, it is for picnic in the park. By the way Rani, whereabuot Shenzen you saw the matching beach bags? I want to add it into my shopping list when i go to Shenzen again :-D.
The fabric stores on the 5/f fabric market hv them. I made some bed sheets fm a lady n she had it. Will check the store # tonight n let u know. They r also making bean bags.