Here you can download the source and executables. Note that the code was designed for, and built on, Linux. Compatibility with other operating systems is not guaranteed! Documentation on how to compile both the program and the externals is provided in the sources.
The current version of WANDA is 2.1. This is a slightly improved version over the one that participated in the last termination competition (although there different first-order termination and non-termination backends were used). Earlier versions are not available, as they were not open source.