You can use the Windows Live Mail address book (A list of contacts, that contains the names, addresses, phone numbers, and e-mail addresses of each of your contacts. If you're signed in with a Windows Live ID, Windows Live Mail uses the contacts list associated with your Windows Live ID.) to store personal information about people you know. If you're signed in to Windows Live Mail with a Windows Live ID (The user name and password that you use to sign in to any Windows Live, MSN, or Office Live sites and services. If you have a Passport Network, Hotmail, or Messenger account, you can use it as your Windows Live ID.) , any changes that you make to your contacts also take effect in Windows Live Messenger, Windows Live Hotmail, and other products that use Windows Live Contacts. If you've never signed in to Windows Live Mail, your address book contains only the contacts that you've added directly to Windows Live Mail or that you imported while installing Windows Live Mail or at a later time.
To send e-mail to a contact or group, when composing an e-mail message, in the To, Cc, or Bcc box, type the group or contact name. Matching contacts and groups are displayed for selection as you type. Or, select the contact or group in the contact list, and then click E-mail contact.
To add a person to your contact list when you receive an e-mail from them, in the message header, click Add contact.
To find a contact, in the Find a contact box, type the name of the contact. Matching contacts are displayed as you type.