The listci command lists all culture infos implemented in .Net. This will display the LCID, name, type, and display name of all CultureInfos.

listci | find " en"

returns

    9 en          N W   English
 1033 en-US        SW   English (United States)
 2057 en-GB        SW   English (United Kingdom)
 3081 en-AU        SW   English (Australia)
 4105 en-CA        SW   English (Canada)
 5129 en-NZ        SW   English (New Zealand)
 6153 en-IE        SW   English (Ireland)
 7177 en-ZA        SW   English (South Africa)
 8201 en-JM        SW   English (Jamaica)
 9225 en-029       SW   English (Caribbean)
10249 en-BZ        SW   English (Belize)
11273 en-TT        SW   English (Trinidad and Tobago)
12297 en-ZW        SW   English (Zimbabwe)
13321 en-PH        SW   English (Republic of the Philippines)
16393 en-IN        SW   English (India)
17417 en-MY        SW   English (Malaysia)
18441 en-SG        SW   English (Singapore)

The list is sorted by the LCID by default, and can be changed using the -o switch. The -t switch restricts the list to certain CultureTypes.