For example, how can I list available GDAL library versions ?
They are not listed on VCPKG packages website neither by vcpkg search gdalcommand.
Try this! it is a quick fix until vcpkg supports pkgs version listing. https://github.com/hamaney/vcpkg_version_finder.
on a related note:
to look up a package by name and get the latest available version of it use vcpkg search <pkg name>
UPDATE SEP-11-2021:
I just found out that you can use the experimental flag x-history. for example vcpkg x-history <pkg name> (you might need an internet connection the first time you run this command).
UPDATE JAN-01-2024:
The x-history option is no longer available.