Firstly if you are here, then you already know that your PST file is your Outlook personal storage table. If you have recently upgraded your computer/laptop and want to run your outlook from your new destination, I probably would not suggest to archive, rather distribute your old data to a new folder. Your current data should be under the Personal folder as a default. Move the stuff you no longer need on a daily basis to another folder, then copy your folders to a backup drive.
So how do you find this illusive PST folder?
From within MS Outlook 2007: Tools > Account Settings > Data Files (TAB)
You may notice multiple accounts. click Open File Location to open the Outlook data folder in Explorer.
OR if you are like me and Outlook has frozen and there is no way you can get into it, even in safe mode….. don’t ask!
Then enter the following in the address bar in Explorer or in the Run command:
Drag the files over to your backup/new location.