Pick up a Dodge's Guide to cruising the ABACOS. It is an invaluable resource that includes marinas, restaurants, lodging, fishing and diving and snorkeling locations and tips.
It also has courses plotted from the major east Florida ports to all of the islands of the ABACOS. The numbers he posts are dead on and will allow you to avoid the sand bars and coral heads that dot the floor of the Sea of Abaco. I would not go without one. You can purchase it at West Marine or Online.
Where are you staying? I may be able to offer some fishing advice.
http://www.wspress.com/detail-cga.htm