Prints out all OLE DB Providers. Don't forget that some are only available if you run 32 or 64 Bit applications

gistfile1.cs

using System;
using System.Data.OleDb;

namespace OleDbEnum
{
    class Program
    {
        static void Main(string[] args)
        {
            var reader = OleDbEnumerator.GetRootEnumerator();

            while(reader.Read())
            {
                for (int i = 0; i < reader.FieldCount; i++)
                {
                    Console.WriteLine("{0}: {1}", reader.GetName(i), reader.GetValue(i));
                }

                Console.WriteLine();
            }

            Console.ReadLine();
        }
    }
}