Buy bulk when it's cheap is the way to go. I spend about $600 more or less around Black Friday buying 22LR, 9mm and 45. Yes, I got yelled at by my wife big time and almost triggered an audit on my credit card bill lol. At the end it's worth it. Combined with the ammo that I had, now I can comfortably say that my stockpile can last me a year or more.
Last time in 2008, the price didn't drop back down to where I am comfortable to buy in bulk until the end of 2010 or the beginning of 2011. Hopefully the stock will come back in a year or so.