This can be done, but it requires writing VBScript code behind the form to:
1) Fill the list when the form opens.
2) Respond to the user's selection, look up the selected contact, and populate the fields with the values from that contact.
It's not a simple task that step-by-step instructions can be provided for, especially if you're going to understand and be able to maintain the code. On the other hand, it's not hard either, if you're willing to learn how to write VBScript code for Outlook. The article at http://msdn.microsoft.com/library/default.asp?url=/archive/en-us/dnarout98/html/
oloutevnts.asp is old but still relevant as a brief introduction.
FYI, there is a newsgroup specifically for Outlook forms issues "down the hall" at microsoft.public.outlook.program_forms or, via web interface, at http://www.microsoft.com/office/community/en-us/default.mspx?dg=microsoft.public
.outlook.program_forms

Signature
Sue Mosher, Outlook MVP
Author of Configuring Microsoft Outlook 2003
http://www.turtleflock.com/olconfig/index.htm
and Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
http://www.outlookcode.com/jumpstart.aspx
> Either you can't do this, you have program it using scripts or macros (which
> I have no clue how to use), or it's an easy fix that I havent been able to
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>
> Kevin
KVSmith59 - 14 Jul 2006 19:15 GMT
Thanks for your help! Now it's a question of finding the time to teach
myself :)
> This can be done, but it requires writing VBScript code behind the form to:
>
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> >
> > Kevin