How can I set up mailing lists?

We have several mailing lists set up on our current mail server, like this:,,,

Moss is the IT technician, he will get emails addressed to webmaster and helpdesk. Jen, Tom and Lisa are from sales department, emails to will be delivered to all of them.

I am a little confused to configure CASG for this, as there is no “Mailing list” in the menu. Should I just add webmaster, helpdesk and sales as users? If so, how can I route emails to respective list members?