""Where is the file that stores my Contacts?
Outlook stores Contacts, messages, Calendar items, and other Outlook items in a data file called Outlook.pst. The default location is drive:\Documents and Settings\<user name>\Local Settings\Application Data\Microsoft\Outlook. Also see Outlook file locations.""
I think you will first have to export them from Outlook to a .csv file before you can import them to your Webmail