What bird species is this? (Heron-like waterfowl from China)
I'd go with juvenile striated heron. I ruled out others such as the chinese pond heron because of the spotted wing plumage and slightly different shape of the patch around the eye. The night heron seems to have a more red eye than the striated heron and appears to have a stubbier beak.

Arkive is a good place to see a lot of pictures of birds, this is a good birding site, and otherwise I use generic google searching (e.g. start with "herons china" or "herons asia") - this at least helps narrow down the search quite substantially and is considerably cheaper than having a library of the worlds bird books!