I started with only 200g to my name on February 27th, 2010. As of April 26th, 2010, I had over 125,000g total liquid, not counting all of the materials I had remaining in my mailbox. I combed the interweb, doing my research, and eventually stumbled upon the Just My Two Coppers blog and started participating in the forums. With their assistance in putting me on the right track and in giving me a place to keep track of what I was doing and how things were going, I managed to reach not only my initial goal of 15,000g but to obtain my ultimate goal of 100,000g before Cataclysm.
I didn't allow myself to splurge on anything until I hit 125,000g so I'd stay above 100,000g when I did so. I've since purchased a basic Kirin'Tor ring, a Gigantique bag for the Achievement (it replaced a Frostweave in my bank), and four Portable Holes for Laurewen. And boy do I need it with all of that gear! This is in addition to the Traveler's Tundra Mammoth I purchased when I was at just under 50,000g.
I'm liquidating all of my materials now, so there's no harm in telling the world how I did it. The majority of my gold was made doing something called the Saronite Shuffle. This is a tactic that was used quite successfully for a long while by many AH goblins, however some recent patches caused many long-time practitioners to turn away from it due to the tanking of Infinite Dust on many servers.
I assure you that I am proof the Saronite Shuffle is a valuable means of in-game income on Nesingwary.
I prefer OmniGraffle for this sort of thing but seeing as I do not own a Mac, MSPaint had to do.
I'd like to condense this just a little bit more if I can, but that can come later.