There are a couple of options:
1-In Outlook you can go to Tools->Accounts and on the Accounts tab you can export the account settings to iaf files and then import them to the new Outlook. Unfortunately you must export each account separately.
2-You can purchase a commercial app like ABF Oulook Backup to backup everything, accounts included. Here's a link: http://www.abf-soft.com/outlook-backup.shtml
3-Do a registry search for one of your email accounts. It should be located in
HKEY_USERS\ \Software\Microsoft\Office\Outlook\OMI Account Manager\Accounts
Your will be a long number begining with "S". Export this key (starting at the "Accounts" level and then import it into your new pc registry.
Cheers.
RW