Code changes:
To make the email property (from Portal_Memberdata) visible you need to go
to the filesystem in the plone instance and edit the following file:
CMFPlone/MembershipTool.py
Find the function:
def getMemberInfo
and in the section where the memberinfo array is created add another line
(not at the bottom of the entries) for the email line like:
'email' : member.getProperty('email'),
You now need to create a template that displays the information.
In the ZMI go to:
portal_skins/custom
and add a page template from the right hand dropdown.
Give it the name 'authorInfoTest' and click 'Add and Edit'
Now delete the current content and copy the template from below:
Test:
To test the page simply go to your plone website and add on the
name of the template along with the userID
e.g,
http://mysite/authorInfoTest?author=webmaster
and you will see the email address of that user