Ammo-can.net has near real time availability of ammo for most Wal Mart stores. It doesn’t look like the website is 100% perfect yet, but it does seem to work. According to the site, my local Wal Mart had limited stock of 9mm Winchester ammo. I went right down to the store and low and behold, there was a box of 9mm.
Direct link: http://ammo-can.net/
