When it comes to gold making addons, as most of you know, there is one that comes before all the rest, Tradeskill Master. This addon will help you make heaps of gold on the auctions house, and will give you a deeper understanding of your servers economy and the whole WoW economy. Learning how to use it well takes time, so read through all the info on their site and maybe watch some youtube videos on how to set up TSM. TSM will help you appraise items, sell items quickly on the AH and buy items that you can resell for a profit, amongst other things. Additionally the addon will help vendor and managing your mailbox, making this the only addon you need for gold making purposes. We will be coming back to TSM in the Auction house part of the guide.
You’re after all the items to make the Super Cooling Module from Shadowmoon Valley, Nagrand or Talador, and the Cyclical Power Module from Frostfire Ridge, Gorgrond or Spires of Arak. Some are worth only a few hundred but I’ve sold a few for over 20k. They drop from any mob in the zone. I haven’t found an optimal spot, but all these zones have plenty of areas with densly packed mobs.
As others have said, there are free alternatives... which is important to consider if the price of the Zygor Guides are a concern. If speed and convenience are more important, then they're worth it. Zygor will take you through the quests in the most efficient way possible, and their customer support and the speed with which they update the guides when changes are made to the game is impressive. I know I went from 80-85 a heck of a lot faster (in /played time) than my co-worker who doesn't have the guides. And we had a bet going to see who would make it first. For me, it was worth it. Your mileage may vary...
I dont know if this exist already, if it does I couldnt find one, but it would be nice to have a guide with the location of all daily quest broken down by Alliance, Horde, Faction, Neutral, etc. I know there can be variable quest for things like Fishing and Cooking but just having the location for those quest givers would be great. If it were a stand alone addon that would be even better!