Just my two cents to the topic. Never ever bother trying to remove water out of somebodys lungs. first you never know how much is in there anyway second the water is absorbed by the alveols in the lungs in a matter of seconds not minutes. Secondary Drowning yes be carefull with that and seek medical check up.
And please no do not ever attempt chest compression on any person older then a new born as long as there is a pulse even if very weak. Even the best CPR is propably just almost as efective as a weak Pulse produced by the heart itself (especialy if the pulse is strong enough to be felt on wrist).
I can recomment the source of the European Resuscitation Council (I am sure there is a compareable institution in the states) They publish Guidelines for almot every possible medical Emergency which are based on lots of studies and a lot of people braking their brains thinking about the best possibility for the patient.
They obviously do not feature how to treat a bo freediver but for example feature a special part about drowning incidents.
Rob
Edited to add a link to the ERC:
http://www.erc.edu/index.php/doclibrary/en/12/1/