Unless you've been trying to buy physical gold, you probably haven't heard about the shortage. Suffice it to say, if you try to buy some at your local coin shop, you'll probably be disappointed.
I first became aware of the shortage this summer, when my local coin dealer was out of all gold coins and couldn't get any from his wholesalers. Since then, I've been able to get Austrian 100 Coronas coins just once. Major online dealers like Kitco are totally out.
Recently there was news of a gold shortage in the Dubai jewelry market as well.
Why are gold prices down significantly from recent highs if there is such a shortage? My guess is that liquidation from huge, leveraged hedge funds dumping futures and ETF positions has pushed down the price below the clearing price for the physical metal. If I were me, I'd use this as an opportunity to buy more gold. I prefer the physical, but when it's not available I'll take the ETF.