As you have already heard with varying degrees of condescension, there is currently an ammo shortage. These happen every few years when something sparks panic in the gun owner community, and every time everyone reacts like it's never been seen before and is the end of the world. I'm not referring to you; if this is the first time you've encountered a panic-fueled ammo shortage, then this is certainly new to you.
What is happening is stupid people being stupid, and greedy people being greedy. Scared and confused people are buying any ammo they can get their hands on, largely due to what they've heard in various rumors and conspiracy theories. Craftier people that have seen this before are buying ammo in bulk, and reselling it through various channels to the panicking masses at an absurd profit. Want to find ammo? Look on Craigslist, where there's plenty to be had from shysters selling at 2-5x the normal selling price.
Sadly, even internet distributors are getting in on the price gouging, and ammo prices from many sources have gone up 50-100%, sometimes more. One can argue that it's supply vs. demand; I contend that it's greedy people lining their pockets from the results of an unspeakable tragedy.
Rest assured, all of this WILL calm down. Manufacturers are upping their production, and in some areas, the panic is beginning to slowly subside. My guess is that everyone will come to their senses once the various proposed gun bans are decisively voted down by Congress. It is worth noting that none of these bills makes ammo illegal to produce or buy.
If I were a less scrupulous person, I'd start an ammunition rental service for national panics just like this. You could buy as much ammo as you want from me at 5x the normal price, and when you had calmed down, you could sell it back to me at 3.5x normal price. That way the irresponsible can go back to being unprepared after the epidemic is over, and I'm left with some money to better prepare for next time.
To get off my political soapbox and answer your question, you can still find ammo online, although usually at inflated prices. Don't feed the Craigslist hustlers; go to
www.ammonow.com, which is a middleman site that routinely updates the stock of various online ammo suppliers with prices and availability, updated minute by minute. For local purchases, go to your Walmart or Academy and ask when their trucks come in. The people in the sporting goods department will by now know this information by heart. Be there at least an hour before the truck arrives. Both stores have strict purchase limits on common calibers (9mm being one), so the first guy in line can't buy the whole shipment. That should get you enough to defend yourself with.
Remember this. When ammo becomes more available and prices become reasonable again, keep a reasonable supply to last you through the next bout of hysteria. You don't need twenty pallets, just enough to defend yourself and have some to practice with at the range.