I've got the same problem, little or no arch in my feet at all. I spent months talking to people about their shoes and even bought a few of the ones most commonly recommended. Here's the results of my research:
1. Arch supports are better than anything. I bought the ones from Walmart. You step on a machine and it scans your feet, then tells you which arch support to buy.
2. I was working 12 hour shifts x 7. The only real solution I found was to alternate shoes every shift. I also wore arch supports two days and worked without them on the 3rd day.
The idea was that every distributes weight and pressure across the top and bottom of your feet differently. After a couple days to get used to wearing arch supports, my feet were still feeling OK by the end of the 7th day. Without the arch supports, my feet would be hurting like heck by the end of every shift. Alternating shoes as well as the arch supports just made things even better