There is a list according to ISO 3166 available at Deutsche Nationalbibliothek:
http://www.d-nb.de/standardisierung/pdf/laendercodes_alph.pdf
A list with English names can be obtained from ISO:
http://www.iso.ch/iso/country_codes/iso_3166_code_lists.htm
Update: With a German localization of the .NET Framework you can use the DisplayName property of the RegionInfo class to get the localized German country name.