Farming cloth still exists! It's possible to farm cloth at any level of cloth! Most server's have cloth inflated so much right now. Here's the prices that I'm seeing throughout my 9 servers. These prices are all per stack of 20:
Linen Cloth - 50-70s

Wool Cloth - 60s-1g

Silk Cloth - 1g-1.75g

Mageweave Cloth - 2g-2.5g

Runecloth Cloth - 2g-3g

Netherweave Cloth - 5g-9g
With the prices so high on Linen cloth you would be crazy to not want to farm these. Obviously Netherweave will be the highest priced cloth, because it's the hardest to obtain. If you are a level 70 you may want to read this and find out which spot would be best for wow gold. Some of the other grinding spots may be better for different classes.With that being said, the price of Linen and Wool is so low on most servers that it's not good for high levels to farm. If you are a lower level there are some great places to farm these and get some early cash rolling in. So for the sake of every level I will list each place to farm.