Yes, you indeed, need to be certified to dive, as far as I know anywhere on the earth. It costs in the vicinity of $350 in Belize, but haven't checked lately. We did the whole course there, but you can do much of it in the States. I've heard, though, that people who learned in a pool had a harder time transitioning to the sea. I don't know. We learned the whole thing there. If you don't want to spend your whole time there reading, you could get it done up wherever you are. Or, my suggestion, do all the reading up there and the actual work down here. To me, that is what I would do. You can do the "Resort Dive" quickie, but I think you will be sorry. They take you to Hol Chan, and the current is rough there. You might not want to dive again. We went with our dive instuctor, just to be doing it, with some of his new clients, and it was a heck of a lot harder than most places we go to. Shallow, but huge current.
Let me give you a very good suggestion here....I'm a little claustrophobic with miserable ears, and I wouldn't be diving now if I hadn't happened onto my dive instructor. I'm sure all of them are great, but do check out Sylvin Forman at Bottom Time. I'm an advanced diver now, and going to learn rescue diving next February with him (Gulp...with my miserable ears, but I'm trusting Seashell's info to save me).
He is the kindest soul. It's a smaller boat so you have lots of personal time with him. In the beginning, when I was all "scardy cat" he literally held my had when currents were rough. Super wonderful guy. If you are just beginning, I could not suggest anyone better. And, he and his brother Allen are two of the first divers certified in the country. There are many great places to dive in this world. The major two reasons we come here so often are because of Sylvin and the hotel I love.
AmbergrisCaye.com 
