You can "create" them on your own. PPM installs precompiled XS modules. Or use CPAN shell to install Mingw for a newer ActivePerl. Or use Strawberry Perl which includes Mingw. Or download the free Platform SDK C compiler (same thing as paid Visual Studio, just no GUI, not like Perl can make any sue of the VS GUI) from Microsoft.
Or do you have non-public, not open source, private XS modules?