Originally Posted by AndreasNYC
Is there a cell company that covers the whole Caribean?
No. All islands are soverign countries and all have seperate telecomunications laws, therefore no privider can do all the countries, but Lime and Digicell and in many, but still you need to buy a new pre-paid SIM in each island. But they are cheap! 410 for the SIM including $10 credit is normal... so its really quite cheap.
but to call home, as others have said, you may be better to use Skype.