Copy the Microsoft User Data folder on your old computer (Old HD/Users/<Your
User>/Documents/Microsoft User Data) to the new computer. Drag it to this
location on the new computer: New HD/Users/<Your User>/Documents/. Choose
to replace the existing folder if you are prompted to do so.
When you launch Entourage your data should appear. If it does not, go to
Entourage -> Switch Identity, and reselect your identity.