There are several shuttle companies in Moab. Here are a few we have worked with in the past.
Make sure you call a few days ahead to make sure they can fit you in.
Make sure to request a pick up here at the Bike Fiend.
Generally the shuttles run twice a day. Early around 7am or 8am and then again at 9am or 10am. Changes are depended on how far you go but general expect about $25 per person. Most shuttles prefer or only take cash. Tips for the driver are appreciated.