Connect other email accounts to your Google Account
Connecting your Hotmail or Yahoo! email account makes it easier for you and your contacts to find each other on Google. Connected email accounts are also added to your alternate email addresses.
Connect your email account
To connect your Hotmail or Yahoo! account, visit the Connected accounts page and select Hotmail or Yahoo! from the Connect an account drop-down menu. While your email account is connected, Google will keep an updated copy of your account’s address book, which makes it easier to find your contacts in Google+.
Disconnect your email account
If you've connected your Hotmail or Yahoo! account but prefer not to be found on Google by this email address, disconnect this account on your Connected accounts page. Then remove this email address from your Google Account settings page.
Find contacts without connecting accounts
To import an email address book without connecting your account, first export your contacts from another email service. Most email services allow you to export your contacts to either a comma-separated values (.CSV) or vCard (.VCF) file format. Once you have exported your contacts you can import your contacts into Google Contacts.