I need to have a multi select box with a list of names for an email form. I would like the names to be listed as a name rather than an email address like so:

Bob
Frank
Nancy
Tom

but once the form is submitted the emails would be directed to

bob@domain.com
frank@domain2.com
nancy@domain3.com
tom@domain.com

The user would be able to select one or more of the names in the list to send the email to. How do I write something that can send out the email to the appropriate people that were chosen when the form is submitted? Thanks