Screw the gold guides, they're akin to the you COULD make up to 10k/month working at home. Take a stroll into the AH and look at prices of saronite ore/bar and titanium ore/bar and cobalt ore/bar, maybe some of the eternal fire/water/air/earth and see if its lucrative to do mining. Take up herbalism too and gather frost lotus for some added cash.
There isnt a secret to "owning" the AH other then some common sense and knowing a trend.
I usually make no joke 2600g from a few hours of farming (about a quarter of that if its got tons and tons of farmers in wintergrasp/basin). To this date I've made probably 50kg, donated 15k towards epic flying for some people, got a travelers tundra for 16k (rep with KT), 14k on a mechano hog, spent 2.5k on relics of ulduar for hodir rep, 8k for grand ice mammoth, like 4k I think it was for the ice mammoth, plus 2-3k on various mounts flying and ground. still have 2k in the bank (after buying mechano hog) and 12,200 pieces of saronite + 1200 titanium ore which ~15g for saronite and 280-400g for a stack of titanium.
As far as addons go Auctioneer/Auctionator/Atlasloot/Carbonite/Gatherer/DBM.. and a few addons that make it easy to repair and sell greys as well as merging stuff into full stacks.
. And Auctioneer so I can see what things disenchant into.
