The Getting Started guide has a lot of good information on building STINGER, what's included in the stable release, and how to get started writing your own code using STINGER.
The Doxygen references and the examples contained in the examples directory of the release package and code repository are good resources.
This is where we will continue to provide Doxygen documentation of the latest release of STINGER. This material is intended as a reference for users of the C interface to STINGER and for those who wish to hack on STINGER and modify it. Although it may be sparse in some places, we intend to completely document STINGER as much as possible and to reach having useful documentation for all functions and structures. The un-embedded Doxygen can be found here.