Esri Courses and Tutorials
Esri Online Courses
Esri offers many online courses on their website. Many of these are free, and Purdue's educational site license covers ArcGIS courses which are not free for all Purdue students and staff. The easiest way to get access to the courses is to create an account on Purdue's ArcGIS Online Organization; you should then have access to the courses.
A collection of various tutorials used to perform a number of common tasks in ArcGIS is available in the from desktop.argis.com at the following link: