Ammo is forbidden on craigslist, but usually you can post it and get a couple hits before someone flags it and they take it down, but by then you've had a couple calls and sold it by then. I did that a few years back when we were shooting sporting clays and I had a couple cases left over and wanted to find a fellow sporting clays shooter who could use the ammo at a decent price.
The WalMart in the town where I work (9,000 people) usually has ammo in small amounts. I asked one of the night guys about it and he told me they get it in on Mondays and Wednesdays and stock that night. I usually stop in around 6:00 a.m. and there's always a few boxes of something. First time I stopped a few weeks ago I picked up 4-500 packs of Federal .22 @ $20.48 each, and 10 boxes of 100 round Federal 9mm @ 19.47 each. After that purchase, they started limiting the purchases to 3 boxes per person. Since then, I usually stop in on Tuesday and Thursday mornings and pick up a few boxes of whatever they get in. One day it's 550 packs of .22 Winchester ammo, next day it's 100 round Winchester .45 ACP for $40.77. This morning I picked up 3 225 round boxes of Remington .22 for $ 9.77 each. There's always a few boxes of whatever they get in left for others.
On a different note, I stopped at Cabela's last Friday and they were stocked with 9mm and had plenty for $ 15.99 per box. I didn't need any so I passed on it. No .22 ammo though. Plenty of .40. I stocked up on Fiocchi .45 ACP online there for around $22.00 for boxes of 50. The online limit was 5 boxes. The guys stocking the shelf said they reduced one whole rack to a 1/4 rack for ammo.
Overall, I'm seeing an increase of ammo on the shelf, so I think we're on our way back. If you positively absolutely can't find ammo anywhere and are willing to pay shipping, drop me a PM and I'll see if I can help you out. That offer is limited to FirearmsTALK supporting members though!!