A dirty, but quick way of building your e-mail Address book is to add e-mail address from their e-mail directly. Mozilla Thunderbird allows doing so in just two mouse clicks, here's how:

1. Open any e-mails you have received and look out for the From: header.



2. Right-click of the highlighted name or e-mail address and from the context menu that appears select Add to Address book.

3. Edit the card and enter other relevant information.

4. Click on OK, to save the changes done to the card.