Taken from MacOS X Hints.
*I ran across a way to look up email addresses on Usenet. I incorporated it into an AppleScript which automates the process. The scripts sends a specially formated email to a usenet server, and searches for the email of the name you submit.
Caveat: Depending on the provided name, this can return a lot of email addresses. Also, you must set the variable theSender to your email address.*
OS version: OS X
set theSubject to ""
set theSender to "your_email@your_host.com"
set theAddress to "mail-server@rtfm.mit.edu"
set theBody to "send usenet-addresses/"
tell application "Finder"
display dialog ¬
"Enter name to find: LASTNAME FIRSTNAME" default answer ¬
"Washington George" buttons {"Okey Dokey"} default button 1
set myName to text returned of the result
tell application "Mail"
activate
set newMessage to make new outgoing message with properties ¬
{subject:theSubject, content:theBody & myName}
tell newMessage
set visible to false
set sender to theSender
make new to recipient at end of to recipients ¬
with properties {name:theSender, address:theAddress}
send
end tell
end tell
end tell