in reply to Search pst files
The advice by jmcnamara is what I'd do today. (libpst looks pretty good!)
But if you can't manage that, you might write a simple VB script to export all the EMail in your .pst file to one or more text files, and then you can use perl to dig through all the data. I had a similar need once, and did it that way. With a little googling, you'll find quite a few VB scripts to export data from .pst files. (I didn't want to learn the Outlook data model, so I just used a script I found on the web to create my text file(s).)
When your only tool is a hammer, all problems look like your thumb.