If you follow goldmaking blogs or livestreams at all I'm sure you've heard by now about selling the ilvl 272 and higher Cataclysm greens. This market has exploded recently with the new SoR 80s; the item level of the gear they get isn't actually very good -- 232, I believe -- so a lot of them hit the AH to get their stats up.
Even prior to SoR, this was a great, reliable market for me. I've been selling these greens for a few months now at a good profit. Prices and volume have now gone up, but a lot of folks are catching on and it's harder and harder to find these really cheap the way I used to. I still search the auction house several times a day, though, and turn up enough to keep my sales going.
At this point, I am willing to spend up to 100g per item, and generally flip them for 475g. The majority of my profits for this week have come from selling this gear. I will buy almost anything (except plate "of the Tiger" items and some things with really bad stats) at the low end -- if it's up for 10g, it's mine. At the high end, I get pickier, trying to choose mostly four-stat items for any slot or three- and four-stat items for helms, shoulders and chests.
You can use Auctionator to search for these items pretty easily, and that seems to be how most folks do it. You just type in a search of Armor/77/80/i272 and voila. However, this search also shows you all the crafted stuff, which I tend to stay away from. I figure the people crafting it can tank my market at any time, whereas sticking to the dropped stuff lowers the competition a bit.
Instead, I use a TSM shopping list for most of it. I'll share it below so you can import it into TSM, but it's really straightforward. I went to Wowhead and looked up the item names for all the gear I wanted to buy, et voila. The only catch is that it sometimes turns up stuff you don't want, namely Rethban Ore and Orb of Mistmantle. But that's only two items rather than scrolling through a page of crafted gear results and trying to remember what you want and what you don't.
Here's the list:
Yup. That's it. Good luck, and don't try to take over the market on my server ;)
Edit: By the way, I don't really do much with the weapons aside from the Toxidunk Dagger, which frequently comes up cheap and sells for a reasonable chunk of gold. The green weapons just don't seem to be good movers for me and the deposits on them are too high, but you can also search Weapon/77/80/i272 as above if you think you'd like to try 'em.