Depending on the type of email program you are using, adding email addresses to your address book is something that is either very easy or takes a few steps. If you use email programs that allow you to do this automatically, you can complete the process fairly quickly. Some email programs add addresses for you, which means even less work on your part.
Choose an email program that automatically adds the people you email to your address book. There are many accounts that do this, but Gmail, Hotmail and Yahoo Mail are three of the more popular, Web-based free ones. If your email program doesn't seem to add addresses automatically, check to see if there are settings under "Address book Settings" to automatically save email addresses. If you don't see such settings, you might not be able to save them automatically.
Click on "Import addresses" in your Contact List or Address Book section of your email program. If your program has an "Import" feature, you can put in your email address and password for another email account, and it will automatically import your contact list. The email servers listed in References, as well as dozens of others, have import features. This process works for Web-based mail systems or computer-based systems like Outlook.
Send a message to someone, or receive an email from someone. Gmail, Hotmail, and Yahoo mail, along with several other email programs, will automatically save the email address and basic contact information of anyone you email, or anyone who emails you.