A relatively long article on people using the language of Shanghai in various forms: 海外年轻人玩转上海方言 (Hǎiwài niánqīngrén wán zhuǎn Shànghǎi fāngyán)

The article mentions a number of Web sites, including:
* wu-chinese.org
* shanghaining.com
* Sinolect.org

To these, I would add
* zanhe.com