If your host has cPanel, you can use cPanel E-mail Manager to connect your WordPress install to your server’s web mail. No, that doesn’t mean you can read your e-mail from WordPress, but you can create and manage the web mail accounts for each user.
The free version of cPanel E-Mail Manager is somewhat limited, though still perfectly useful: All e-mail account management must be done manually; if you want to automatically add a new e-mail address for each new user, automatically notify them via their primary e-mail, or manage mailing lists, you’ll need to upgrade.