Two remarks.
1. You should learn to use google. A search for outlook -express effectively removes all info on outlook express from the results, and searching for outlook 2003 does more or less the same. outlook[/b alone gives much irrelevant results, indeed. That's exactly like what happens if you search for bush if you want to search for george bush only. Agreed?
2. http://support.microsoft.com/kb/287070 tells it's in a .pab file (personal address book). And if this is a critical file for you, it must be on your backup, because you stated you backed up all your critical files. I hope this statement turns out to be true.
Hope this helps.
Kees
Okay, my computer crashed in flames with a BSOD. Naturally I had all my critical files backed up and decided it was time to start anew. So I reinstalled Windows XP.
I put the .pst files in the proper directory and clicked on Outlook 2003. I finally got my messages imported, but my address book is gone. It did, however, make its way to the "Contacts" list. All the data are there, but nothing in my address book.
Searches in Google showed me that to the rest of the world, when one says "Outlook," they really mean "Outlook Express." Nearly everyone, I found out, thinks of Outook Express as Outlook. In other words, there doesn't seem to be any information.
Where is the address book found, and how do I get it back?
Thanks!

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic