Introduction Training Videos
Commercial
Pluralsight has an introductory training course available here: http://pluralsight.com/training/courses/tableofcontents?courseName=orchard-fundamentals
The first part of the Pluralsight video course is free, and subsequent episodes require a subscription.
Free
Dojo Course
Course for beginners interested in developing on Orchard, starting with how to use Orchard from the UI.
Orchard CMS for Absolute Beginners
Orchard CMS for Absolute Beginners by Abhishek Luv
Orchard CMS Tutorial : Recipes in Orchard CMS
Orchard CMS Tutorial : Recipes in Orchard CMS by Abhishek Luv
Orchard CMS Theme Development For Beginners
Orchard CMS Theme Development for Beginners by Abhishek Luv
Orchard CMS Tutorial : Workflows in Orchard CMS
Orchard CMS Tutorial : Workflows in Orchard CMS by Abhishek Luv
Introduction to Orchard 1.5 by Sébastien Ros
A 4-part series by Brent Arias:
Introduction to Orchard 1.4 by Bertrand Le Roy:
Hands-on Labs
Kris van der Mast made his hands-on lab material available to anyone for free: http://www.krisvandermast.com/downloads.html
Conferences
CodeStock 11
Grow Your Website using Orchard by Jason Gaylord
TechEd 11
Orchard 1.1: Build,Customize,Extend,Ship by Sébastien Ros
TechDays 11
TechDays 11 Basel - Develop and maintain CMS solutions using WebMatrix and Orchard by Ken Casada
Mix11
Deconstructing Orchard: Build, Customize, Extend, Ship by Brad Millington