We used a tour outfit called Normandy D-Day Tours. The guides name is Guillaume Marie, and he was excellent. His website is below. If he is not available, he will recommend another guide. You can read his TripAdvisor reviews below, and you will see that he is excellent at what he does. Expect the prices to be fairly high, several hundred dollars for a full day tour. We were a group of six, so the price per person was reasonable. In my opinion, it was worth every penny. The stories, history, historical facts, plus they will drive you everywhere, all day, and pick you up and drop you off right at your hotel or B&B. We looked at this as a once in a lifetime opportunity and went with the best, most highly rated guide we could find.