Great video series that fully explains Organic Groups and memberships. A must for Drupal based membership sites
Drupal 7 - Populate Drop Down select from DB in Form API - Stack Overflow
CiviCRM Starter Kit - Download and Install the Current Versions of Drupal and CiviCRM
If you want to add inline image insertion to your WYSIWYG editor in Drupal, you need to build a bridge between the editor and the Drupal media manager. This is done using the IMCE bridge.
If you need to take Drupal Mobile
Selling scheduled anything in Ubercart.
Inline Entity Form can help working with the Drupal Data Base much easier.