One of my favorite time management authorities is Julie Morgenstern. Her latest book, Never Check Email in the Morning, is described in her September newsletter.
Below is a quote to entice you to read more at her website feature From the Inside Out e-newsletter.
"The most dramatic, effective way to boost your productivity is to completely avoid email for the first hour of the day. Instead, devote that first hour every day to your most critical task. When you devote your first hour to concentrated work, the day starts with you in charge of it rather than the other way around."