hi!
here you go for a start..
http://www.oropila.com/karte/brac-l.jpg
http://www.oropila.com/karte/brac-d.jpg
i don't know much about brac, i've been there as a kid but as i heard from some people it is really crowded in july and august( as all the croatian islands). anyway if you have a boat you should be able to find some good spots.
in croatia you need a permit which you can buy in the local harbour office( ask for it imediatly after you get off the ferry as it is usually located on the same spot.).
the prices are: 60 kunas/day, 150/ 3days, 300/7days, 700/month. make sure that you have it with you when you go spearing. you can kiss goodbye all your gear plus fish and pay a fine of 3000 kunas if they catch you. the diving buoy is also obligatory but if you hunt in shallow water you might get away with having no buoy. you can carry up to two guns with you, one attached to the buoy.
have fun!
