You can easily add any address (To, From, or CC fields) from any message to Outlook's Contacts by selecting the address in an opened message or preview pane header and choose Add to Outlook Contacts. If you have the message header hidden, you'll need to display it first - in an opened message, look on the View menu, in the preview pane right click on the border separating the preview from the message list, or for the reading pane, right click anywhere on the gray border, then choose Header Information.