Sure can!

First, find the "Address Book" group in your Messenger list (scroll down if you need to – the "Address Book" group is the last group in the list). Click the triangle next to "Address Book" to open the group.

Now, locate and click a person in your "Address Book" group. Check it out:

Depending on their setup (or how much of their information you’ve got), you can IM them, text message them, email them, or place a computer-to-computer or computer-to-phone call.

Please Note: You must have the required information in the "Address Book" field to perform one of the above functions.