This was a farming spot that I made vastly popular on YouTube sometime last year.  It is my FAVORITE farming spot of that era, simply becuase it was an old world farming spot that allowed you to hit almost 3 different markets.  With this spot you can get cloths:  Felcloth, runecloth, and mageweave. Herbs:  Goldthorn, ghost mushroom, goldclover, and fadeleaf.  World drops: rich purple shirt.  AND a plethora of transmog from a single run.  I literally had some pulls where I came out with 17,000g in item value for 10 minutes of farming.  It was insane – actually it still is.  Anyway If you have a druid or monk, then this is an awesome farm to hit ESPECIALLY if you are on a high populated server.  Generally just pull the entire instance, and circle it back around the front.  Mega gold to be made here.
Herbalism is also a good source of money. Herbs are required by alchemists and scribes. Unlike ore which is found only in rocky areas, herbs can be found in many places. Be sure to check on the auction house for what herbs are in demand for a high value; often a lower level one is very valuable, so you can farm an area you already know for quick money.

Battle for Azeroth, despite the endless grind, has been an exciting expansion this far. However, raids and additional content are what makes the game great. Blizzard has made the entry level into the new expansion welcoming for new players and some die-hard critics have shared their concerns with the current direction Blizzard are going with making the gaming “easier.”
It surprises me how this farm was not made public until Legion.  It literally slipped through our sights all throughout WOD, where admittedly it would of been a GREAT replacement for the infinite embersilk spot that was quickly nerfed.  Anyway, this volatile fire spot takes place in twilight highlands in the humboldt conflagration area – which is a small fire bed with about 20-30 elementals roaming around.  Each time you kill you have a chance to recieve volatile fire which is worth 50 – 100g per drop.  However, according to my test, the volatile fire has a higher drop chance than the volatile water.  I believe this has to do with the popularity of the volatile water farm in WOD, it's popularity may have of gotten it stealth nerfed.  Sad to say, but this spot is slightly better in my opinion.  REMEMBER to use a potion of treasure finding.
The most simple thing is TradeSkillMaster. This AddOn shows you quite an amount of information in the items tooltip. In my opinion, DBRegionMarketAvg the best source. It tells me the price, an item was posted on all EU realms in the last 14 days. Why not DBMarket? DBMarket only shows you the items value from your server in the last 14 days. This value often gets manipulated. Some people start to post an item with a 500g value for 500.000 Gold on the auction house for several weaks. As a consequence, DBMarket is rising towards 500.000 Gold.  If you use DBMarket with 100% and post your item for 500.000 Gold, nobody will buy it.