Do you want to make a Distribution list using a list of addresses found in another file? While the recommended method is to import the addresses to contacts and assign categories so you have an easy to manage dynamic DL, you can easily copy and paste the addresses into a DL form.
The addresses need to be in semi-colon delimited format or one address per line.
I don't know if there is a limit to the number of addresses you can paste at one time, I've pasted as many as 35 at once.
Works with OL98/2000 Corp mode or Outlook 2002/2003.
See Using Custom View Data if you need step-by-step instructions.
Learn about
Dynamic DLs in Tip 10: Dynamic Distribution Lists