There are innumerable places to buy hairy crabs in Shanghai when its in season. Three places rated highly on Dazhongdianpin are: 1. Huang Ji Yang Cheng Hu Da Zha Jie Zhuan Mai Dian (黄记阳澄湖大闸蟹专卖店) 2. Cheng Long Hang Xie Wong Fu (成隆行蟹王府) 3. Xie Xie (蟹榭) From October to November, you can find it in most supermarkets!