HI, from our experience as an e-learning content production company, some of the more popular authoring tools include Trainersoft, Kallidus, Atlantic Link and Lectora. There are literally hundreds of providers and most Custom Content Producers  like ourselves have their own in-house tools which we share with customers to co-produce and maintain content. Ours is called REALMS. This webpage shows the diversity on offer http://www.e-learningcentre.co.uk/eclipse/vendors/authoring.htm