Binary: download the binary version from SourceForge, extract the zipped folder and simply double-click on KS-DDS.bat! You need the Java runtime. If you want to test the content-sharing feature, you can choose between a custom desktop search application, bundled with this distribution, or download Google Desktop Search.
Source: to install the source version, first download the source version of Limewire. Then, you can download Distributed Desktop Search from SourceForge and compile it. Again, you need the Java runtime and, if you want to test the content-sharing feature with Google Desktop Search, download it from Google site.
From SourceForge you will soon be able to download also documentation and other material about the project.