The key here is protection for focused attention. Limit your telephone time and access. Set aside certain periods of the day to receive and make telephone calls and answer email. Set up a voice mail or one-message system that is linked to several phone numbers. Get caller ID and learn to look at it before answering the phone.
Email is a wonderful time-hog.
Delete your sent mail on a regular basis. If you want a record of email you send, send a blind carbon to yourself and file it where it's easy to retrieve. Limit the time you spend on email each day. Customize it to meet your own needs. Make sure you transfer all information from month to week to day.