While Harbour is still in development the preferred method of getting a Harbour binary is to download the source and build it yourself because this aids the development effort.
However, the Harbour developers also appreciate the efforts of people who don't want to develop Harbour itself but do want to test it and report bugs. To this end some people maintain Harbour binaries that are ready to be installed.
Please keep in mind that the following may not be the very latest cut of Harbour (Harbour changes by the hour while in this early phase of development) and that some platforms might be better supported than others. If you see that a platform isn't supported or is out of date please consider stepping in and making available binaries for that platform.
If you can't find binaries for your environment via the above links then this means that someone isn't contributing for that environment, perhaps you'd care to step in and fill that gap?