Try a search on your system for "Outlook.pst" just in case. If that can not
find it, there are a couple of commercial undelete programs you can try.
If the pst contents (mail, addresses, calendar, etc.) was of no value to you
and you just want to create a new pst file, go to control panel and double
click mail. Click on your profile and then properties, click on data files,
click on add. This will get you into your default location for pst files.
You can just create a new outlook.pst file here.
Even on home pc's backup can be essential, as you just witnessed. You might
want to spend a couple of hundred bucks in an external drive and some
backup/image software. That way you can retrieve data when you accidentally
loose it.