How to create/use e-mail distribution lists (aliases) in Mozilla Thunderbird
Creating e-mail distribution lists
Choose Address Book from the main menu.
From the Address Book menu choose New List.
Enter the name of the list and the e-mail addresses
you would like to include in the list.
Then click on OK.
Using e-mail distribution lists
Open a new message composition window. In the To field, type
in the name of a list. When you send the message, each member of the
list will receive it.