No other major SaaS company in the world could get away with this approach to
paying customers. Not only Google offers no user-friendly tools to add shared
contact to the paid version of Google Apps. They offer no tools. Period.
Here is the only information available to email administrators:
Administrative management of non-employee contacts now available
Premier Edition administrators can now add contacts that aren’t employees
of their own company to the contact list that each user can access in the new
standalone contact manager.
First, create an XML representation of the shared contact to publish. This
XML needs to be in the form of an Atom element of the Contact kind, which
might look like this: