Hi I'm new to the forum and read few posts about making gold in AH

Since Cata launched, I've been making quite a lot of gold from single alchemist by transmuting. Then I have many alchemists right now. I thought I was making a lot of gold until I come here and see some make as much as 20k a day.
I left wow in March/April and came back in August. The problem is that I found some of the prices went down a lot. I wanted to start JC gem cuts, but there are a lot of competitors now. I read about ore shuffles, but from what I calculated from the prices of the products in my realm, it doesn't seem like a good way to make gold, albeit all the tips from all the websites. JMTC gives good tips for ore shuffle but there is no date where the idea was posted. It just says 8:00am posted, which is not very useful for current AH.
I have a person in my guild doing elementium shuffle. But he mined the elementium ores himself for 6 hours and make 10k a day according to himself. While its tempting to buyout the elementium ores, prospect and sell for less than the 10k profit margin, it sounds very risky for me.
I'm just wondering if some people still doing ore shuffles/milling/inscription whether that is still making a lot. What happen to the products you don't sell? Do you just vendor the whole lot?
Appreciate for all your input and ideas.
Circus