I made this Silk Cloth Farming guide to help out players who want to farm the cloths instead of buying them from the Auction House. I decided to search for places with high density of mobs which I can kill and drop [Silk Cloth]. I traveled around Azeroth, and after a while I made a list of places.
Thousand Needles - Horde or lvl 50+ Alliance
Westreach Summin at Thousand Needles is almost the same as New Thalanar, but the mobs are a bit more spread apart. Grimtotem Pillagers are battling with Summit Defenders and they instantly respawn after the number of mobs in the are are getting low, which means you will never run out of them.
Note for Alliance players:This place is close to a horde town, so lower level alliance players should not go there, but for higher level alliance players it doesn't really matter as long as you have some kind of AoE ability, you will oneshot mobs anyway. You should only farm here if you oneshot the guards because the guards drop no loot.
The Dwarfs and Troggs inside the cave that leads to Uldaman drop a lot of Silk, so this is a great alternative if you can't farm at the previous places mentioned in the guide. Don't forget to clear the mobs outside the cave too! There are a lot of mobs up on the cliff to the right from the cave entrance.
The respawn rate is not that fast, so if you have a class with high mobility, you might clear the mobs too fast and you have to wait for respawns. (if this is the case, you should clear Uldman once while you wait for respawns)
Blackhoof Village in Dustwallow Marsh is also a decent place. The mobs drop 1-3 Silk Cloth and they respawn pretty quickly, you can keep running from one end of the camp to the other and farm Silk Cloth.
When you have enough Silk Cloth, go to my Mageweave Cloth farming page.