The file you need to back up is your Personal Folders file (*.pst) It's
where all the mail, calendar, contacts etc are stored.

Take a look at these pages for info on Outlook data backup:
http://www.slipstick.com/config/backup.htm
http://www.howto-outlook.com/Howto/backupandrestore.htm

Microsoft has a utility that allows you to backup your personal file
folders in Outlook ( believe it is available for 2000, 2002, 2003 ).  You
can use this, store it in your MyDocuments folder and back up with your
other data onto cd.

Go to microsoft.com and search on     backup outlook     and  you should
find links for this.   This is an add-in which you will need to download
and install ( takes about 2 minutes ) and you may need administrator rights
to do so.  On Outlook 2000, you can specify the frequency to backup in
number of days and can specify the folder to backup to, and I suspect
2002/2003 are similar.  This utility will backup ALL of your outlook
folders including contacts, inbox, outbox, ( and I suspect deleted items,
so you may want to empty it regularly ).  I don't remember if you can
specify only certain folders.

Another option that you can use is the import/export function under the
"file" option in outlook.  If this function has never been used on your
installation, you may need the installation disks, and again you may need
administrator rights to install it.  This method is more cumbersome, but it
is more flexible as well.  You do each folder independently, but the files
can be saved in a text document.  As before, you then copy the file(s) from
your MyDocuments folder onto a CD.  Do the following (again for 2000 so
2002/2003 might be slightly different):

-   File
-   Import/Export
-   Export to a file
-   Next
-   Select the file type you want, Comma Seperated Value (CSV) is usually a
good choice, for you can then open the file in a text editor or Excel and
it is importable to other applications.

-   Next    ( If this is the first time to use this, you will be prompted
to install it.  Insert the Office installation disk and click OK )  after
install....

-   Select the folder you want to export ( we'll do Contacts for here )
-   Next
-   Browse to your MyDocuments folder where you will store the file and
give it a name, ie..  contacts  ( a file type of either DOS or Windows CSV
should be shown in the "Save as type" box )

-   OK
-   Next
-   'Export "Contacts" from the "Contacts" folder' should have a check mark
-    Finish

Repeat the above for your inbox, outbox, notes, etc... if you want.

To restore from the CSV file, you use the same import/export engine, but
you will select to "Import from a file" when you get to that point in the
wizard.

Hope this helps.