Sources for windows ISO files
Drop .chef/plugins/knife/source_ingredient_windows.rb into your .chef/plugins/knife directory and run:
knife source ingredient windows
:file_cache_path and :data_bag_path must writable and might need to be set in your knife.rb
The versions of windows encoded in the plugin will be downloaded into your file_cache_path and your data bag path will get a windows directory created which will be populated with data bag items for each version of windows that is downloaded.