I almost never see 9mm either of the two local SuperCenters. Maybe I'm not going often enough.
I can get .40 all day long, it seems. WWB .40 is down to $20/50. 100pk is $37. This is as cheap as I can remember seeing in the last 18 months or so. I think pre-panic price for .40 was $17/50, so not too bad now.
On the other hand, once you find what you shoot well, carry as much ammo as you can comfortably carry. While the average gunfight might use less than 5 rounds, if you find yourself in a gun fight, the law of averages has already abandoned you.
I've had good luck with finding 9mm on the shelf at the Walmart on 31 in Greenwood, going in early in the morning (anywhere between 6am and 9am). Best luck has been Saturday and Sunday mornings, though I've found some on Monday and Wednesday before as well. It's usually a crap shoot, but it's been stocked better the last two weeks from my experience.