A wide range of Barbados' Maps are available from  Pocket Flyers Inc

These maps are extremely well defined and you can print them and bring them along to help you when you arrive.

Also available are online interactive maps:
http://Barbadosbymap.com, offering maps of almost every poit of interest including, hotels, apartments, guesthouses as well as all activities and attractions 

http://barbados.org/maps.htm combines artistic maps with google earth maps, also for just about every point on the island.