• Documentation - read about the details (includes a "Getting Started" tutorial). Many parts of the documentation have not been updated for the 2.x version, we're working on it.
• EMF Newsgroup. Please add a [Compare] tag in your forum entry.
• EMF Compare Bugzilla - review and create Bugzilla entries
• File a bug - file bugs and feature requests

The EMF Compare team can be contacted through the official Eclipse EMF forums and newsgroup. Yet this form of support may not meet daily needs of an enterprise adopter as far as response delays are involved.
Most of the developpers of EMF Compare are from Obeo, and are then the best source to provide competent and professional support :

• On demand support (based on hour consumption)
• Long term support (integration and maintenance inside your Eclipse bundle)
• Coaching
• Customizing EMF Compare for your needs