I make a ton of gold from my professions like most people. I also make a huge amount for flipping items that are listed cheap on the AH for higher prices. This is a very simple way to get insane profits with little work.
First thing you need is Auctioneer or a similar addon. If you already have this and run scans on a regular basis....GREAT! If not, start running scans. For auctioneer, the best way to run scans is the quickscan function. It will be a little double arrow that looks kind of like >> at the top of your screen. Run them at least once a day.
The second thing is to go to the Consortium Forums and look up how to set up a snatch list and what items to put on it. This can take quite a bit of time.
Next thing you want to do is go to the search function on the bottom tabs. Then click on Snatch and then click the search button.
This will bring up all available items on the snatch list that are below your threshold.
Make a determination if these are worth buying and reselling based on your server.
After the snatch search, I then go to the Resale tab and search again. I first sort it by profit. I then check the percentage of the normal price of that item. I generally like to buy items that are a very low percentage (generally under 20 percent of the normal value).
My favorite items to buy for resale are recipes and low level blue items. I buy tons of blue items in the 1-10 gold area and flip them for 50-200 gold each.
Recipes is by far the best. After I am done doing a resale search, I go into the regular auction tab and do a manual search of the recipes. I will generally buy out anything in the single digit for a percentage. I buy a ton of recipes for between 1-5 gold and sell them for 25-150 each.
Sometimes you get really good deals. I have flipped around 5 of the Cata bracer enchants for probably 20k profit. I picked up one last night for 15 gold.
This is a no brainer way to make gold and take almost no effort.
Hope this helps.