Get there on your own - I was traveling with a large tour company through Morocco, we were stopping at Ouarzazate for the night and were given the choice to book though them a quick visit to Ait benhaddou for the next morning (pretty expensive quick visit), so, if you're coming from Marrakech to Ouarzazate or if you're already there. Go to the "Station Grand Taxi Tabount" a couple of streets back from Place Al-Mouahidine. There will be several taxis stationed there so you can ask prices and haggle for a ride to Ait Benhaddou, we were 5 people riding the taxi and it charged us 100 dirhams, but could probably you can haggle the ride for less. Ait Benhaddou is 35-45 mins away from Ouarzazate, and you could ask the taxi to wait for you in case you plan to return back to Ouarzazate. I would spend a night at Ait Benhaddou, since they told me the sunsets are pretty awesome to watch, which I did not get to see, you can also ask the taxi to take you to a lookout of the city which gives great views of the whole city from afar. Staying for the night would give you the opportunity to visit the town early in the morning without too many tourists and get better photos.