You can fetch the source code from GitHub or fetch a self-contained binary image using the following links:
Note that pgloader is easy enough to build from sources, see pgloader INSTALL.md file. For RPM based systems, see also the bootstrap-centos7.sh script that prepares your build environment so that building is then just a git clone then make away.
Building for the Windows™ Operating System is easy enough and the platform is fully supported. Please report any problem there as usual, via the pgloader issues facility hosted at github.