If you have Entourage 2004 with the latest updates along with Mac OS X
10.4.3 or later, go to Entourage > Preferences. Under "General
Preferences", click "Sync Services". Check the option to "Synchronize
contacts with Address Book and .Mac". The data should soon synchronize.
If you have Entourage X, try this. To import contacts from Address Book
into Entourage, drag them to the Desktop, and then drag them into the
Entourage Address Book window. Beware that not all fields will transfer
correctly using this method. For a transfer that preserves more
information, use Paul Berkowitz's "Sync Entourage-Address Book" script. It
is not free, but it does include a free trial period.
http://www.scriptbuilders.net/search.php?search_str=Sync+Entourage-Address
