So, for whatever reason, you want to know what the LDML that the CultureAndRegionInfoBuilder needs is for all the locales for the box.  It's pretty trivial, but:

using System;
using System.Globalization;

class DumpAllLocales
{
    static void Main()
    {
        foreach (CultureInfo culture in CultureInfo.GetCultures(CultureTypes.AllCultures))
        {
            try
            {
                // Skip invariant
                if (String.IsNullOrEmpty(culture.ToString())) continue;

                // Get the CARIB, watching out for neutrals & customs, and call save
                CultureAndRegionModifiers flags = culture.IsNeutralCulture ? CultureAndRegionModifiers.Neutral : CultureAndRegionModifiers.None;
                if ((culture.CultureTypes & CultureTypes.UserCustomCulture) != CultureTypes.UserCustomCulture)
                    flags |= CultureAndRegionModifiers.Replacement;
                CultureAndRegionInfoBuilder carib = new CultureAndRegionInfoBuilder(culture.ToString(), flags );
                // This will blow up if the file exists already
                carib.Save(culture.ToString() + ".ldml");
            }
            catch (Exception e)
            {
                Console.WriteLine("Error for culture " + culture.ToString());
                Console.WriteLine(e.Message);
            }
        }
    }
}

put this in a .cs file, add .Net to your path, compile and run:

%windir%\Microsoft.NET\Framework\v4.0.30319 /r:sysglobl.dll dumpAllCultures.cs

dumpAllCultures.exe

-Shawn