I second NOAA charts. They are the official chart provider for US waters and are free to download. When you download from NOAA, you get a corrected and up to date chart. You have to download weekly if you want your charts to be current
. You can also check out NGA. The Navy
uses NGA charts and are free to download for US waters. NOAA charts are better though. For larger scale charts in the Bahamas
, you might have to purchase
from somewhere. Bluewater Books
in Fort Lauderdale
should be able to point you in the right direction.