The compiled binaries and associated JavaScript files for WebAudio Csound can be downloaded from csound.com. These files are also provided here, in the PAW repository.
A number of WebAudio Csound examples are available.
Reference documentation for the CsoundObj API and the csound.js frontend can be found here.
A simple python script running a local web server for development is also provided.
These are the workshop notes, which refer to Csound-powered HTML page templates.