DrupalBook project was started in 2010 as free online book about creating sites on Drupal. It was originally created in Russian and placed on DrupalBook.ru domain, but now you can find Russian versions of articles and videos on drupal.ru site in documentation section:
http://drupal.ru/docs
DrupalBook contains articles about Drupal site building and module development. Some articles have screencasts, but they mostly are in Russian.
Also DrupalBook will helpful for building online stores on Drupal Commerce and Ubercart as for programmers, as for site editors.
English version of DrupalBook is available here:
https://drupalbook.org/