I would like to hear from CAD users to what their favorite Training Books for AutoCAD are and which ones are the easiest to learn from. I am updating from AutoCAD 2012 to AutoCAD 2015, the newer version has "The Ribbon" that I am not familiar with. So I know there will be a big learning curve. I work in the architectural field, so books leaning towards that field will better suit my needs. I will probably buy more than one training book. I see two books on Amazon not sure how well they are: Mastering AutoCAD 2015 and AutoCAD LT 2015 by George Omura & AutoCAD 2015 and AutoCAD LT 2015 Bible by Ellen Finkelstein. Does anyone know if they are for architecture? Is one better than the other for ease of learning? Any feedback will be appreciated. Thanks