CamBam supports two forms of automation : Scripting and Plugins.
Some example scripts are provided in the \scripts sub folder of the CamBam installation directory.
Refer to these forum sections for more information and examples of scripting.
Scripts and Plugin Help
Resources - Scripts and Plugins
Plugins are .NET .dll files which can be written in a variety of supported .NET languages such as C#, Visual Basic, C/C++ etc.
Some example plugins are provided in the \plugins sub folder of the CamBam installation directory.
For a fantastic introduction to writing user plugins refer to MrBean's thread on the CamBam forum:
How to write a CamBam plugin
Note: - The way plugin menu handlers are registered has changed in version 0.9.4.
For more information, refer to the What's New? section.