Quick informal survey of various gun websites...
9mm, .40, .223/5.56 and .308 ammo are hard to find in anything other than high end hunting/target/defense loads - $1 per round kind of stuff. Of these, .223 is the least common to find in stock. Less common AR loads like .300 AAC Blackout or 6.8 SPC are also tough to track down, despite their usual per-round cost.
I'm surprised, but .45 ACP is fairly readily available - though I guess it makes sense that 1911 shooters aren't as freaked out about potential legislation.
7.62x39 and .30 carbine look to be available without too much trouble.
.22lr is fairly readily available, but you may not be able to get a hold of a favorite load.
AR magazines are out of stock most everywhere. Mako Group has steel made-in-Israel magazines for under $20, which is the best deal I've seen in a while. Looks like private sale price on PMAGs is a little bit under $40/magazine. Midway and Brownells are taking backorders, but expect to wait a month or six to see your magazines arrive.
Glock magazines? Good luck.
What is available? 12 gauge, no problem. Hunting cartridges like .30-30, .243 Win, .30-06 and others are out there a-plenty, too. In handguns, the as mentioned .45 ACP is out there, along with .38 Special, .357 Mag and other revolver cartridges.
Prior to the panic, the "big 4" survival firearms were an AR-15, Glock 19, Remington 870 and Ruger 10/22. If you were forced to choose from what's currently readily available, a Remington 870, 1911 in .45 ACP, a .22 of some variety (10/22 if you can find one!) and a nice scoped bolt gun would probably be the new big 4. Or a .357 revolver and a matching lever gun instead of the .45 and bolt gun.
What are you seeing in your neck of the woods?