Jeff,

Use a drop-down list box. Right click, select Properies then from the
options offered select  if you want to provide the values literally or
choose one of the offered lookup options.

Or perhaps you were asking a different or more specific question?

Andrew Watt
MVP - InfoPath

Enumerate a drop down with your addresses.  Right next to the list box
insert a Hyperlink control.  In the Hyperlink control properties dialog, set
the "Link to" section to "Data Source".  Use the following XPath:
concat("mailto:", my:EmailDropDown, "@company.com").

This will prepend the 'mailto:' protocol to the aliases listed in the drop
down and append them with '@company.com'.

In the "Display" section of the dialog, select "Data Source" and use
my:EmailDropDown as your source node.

Now when a user selects an alias, the email address will be populated in the
Hyperlink box and the user can click on that to launch their default email
editor.

--josh bertsch