Use the Linux equivalent of either a search or a directory with recursion command. Search for either a specific file name which you remember or for *.doc. or *.xls
I would try first in the Documents and Settings folder. If that doesn't work search the whole hard drive. There is also
the possibility that your folder is stored on another partition or drive. The fact you see only the basic system folders:
All users;Default User;LocalService;NetworkService in Documents and Settings leads me to suspect your profile
and files are stored elsewhere.

The my documents under all users is shared documents. The default user is the template used to generate a new user.