I'm sorry, QwikSilver. Unless you have a backup of the PST file you'll have to rely on what emails have been saved on the email servers. If you can setup your email accounts as IMAP, you might find quite a few are available. As to your POP3 accounts, once you re-set those up in Outlook, anything that hasn't been deleted from the server will re-download.
Jimbo's reference to the pfbackup.exe is a great solution and works in Windows 7 x64 and Outlook 2007 and 2010 32 bit but not with Outlook 2010 64 bit. If you encounter any issues with installing and using that add-in, please let us know. I did a lot of troubleshooting on it before discovering it won't work with the 64 bit version of Outlook 2010.