Send Email shows you a selection of Email Addresses:
Email Address on the Customer
Email Addresses from Contacts for the Customer
This Solution describes using this dialog. (6503)
Send Email includes:
a checkbox for selecting each recipient
Send - a pulldown for setting To, Cc, or Bcc for each recipient
Name - the name and email address of each recipient
Title - the title for each recipient
Type - the source of each recipient, Customer or Contact