The basic email settings for your account...
Incoming Mail server: mail.yourdomain.com
Outgoing Mail server: mail.yourdomain.com
username is your email address.
The password is what you set when you added the email account.
You can download automatic configuration settings from the control panel, go to 'Email Accounts', scroll down to find the email address and click on "Configure mail client". This will provide a list of common email programs that can be setup automatically.
There is also more details here on email settings on this same page