Responsible Purchasing Network (webinars)
Pennsylvania Green Purchasing Video (~15 min online video)
Getting Started Buying Green (online video -three segments, State of Iowa)
Green Purchasing Accredited Professional (series of online green purchasing courses by The Green Standard)
USGBC LEED Education (webinars, online trainings, classess related to the LEED green building certification)
These groups offer a variety of sustainability topics, but will occasionally offer procurement-specific sessions.
The Natural Step Network
University of Oregon Continuing Education – Sustainability Leadership