"Living off the chain" is taking fast all over with the decline of jobs and the rise of prices of everything and thus it is getting more and more strictly controlled.
Marinas across the country are clamping down on their 10% rule/law (usually its state, county or city law to have no more than 10% of vessels at moorage being occupied) and usually 10 years or older and under 25 feet are not acceptable in marinas or livaboard.
If you can talk them into letting you rent a slip and are caught living aboard you face fines, impoundments and even possibly arrest - more so you can be blacklisted from entire regions for such unruly practices. For example I am not allowed to posses a boat in the Oakland estuary the fucking artsy hipster trustafarians will call the law on me and fuck my shit up if I try to start up a homebase of any kind. thease people do not forget people easily, 'specially if you stand out as potentially dangerous to the way of life.
IF you can manage its far better than living in a car, squatting or housing. There is less laws on the waters while titleing, registering and insuring is almost alwase compulsory it can be overlooked as long as you appear presentable (I.e., not flying a jolly roger, pissing off the side of your boat, drunken screaming at all hours - etc.,) LOW PROFILE!!!
ALSO because of the financial state of the world more and more boats are being scuddled and abandoned. Johnny proper and Jane Doe rather than paying 1000's every year for mooring and insurance on top of property taxes and such on there two house and 5 cars will quietly make that 33 foot sloop disappear by taking it out one Sunday afternoon and holing the hull with an axe or improvised charges, maybe a shotgun to the interior hull and dinghy it back to shore or they might pump it full of water and claim it sunk of accidental causes and reap 100's of 1000's of dollars in insurance payoffs, this is why you will not hear of free or near free boats - its all real hush hush I have already outlined all this in my age old and super controversial thread Modern day piracy and crew poll.
As for underground pirate ports, well you have to sail to them stumbling uppon them by mistake or you have to know someone who knows something I know this guy that has connections in the Caribbean and I know some people up in Alaska and they would not make a show of there lifestyle on this site or any other for fear of what we would call "oogles" blowing up spots and making shitstorms materialize. these are for the most part people with money who choose to shit overboard rather than moor and flush their tanks to save a buck they are elitist fucktards and will rather than help you call the harbor patrol on you - imagine if every other rail ryder was to do that?
Plus if you have any semblance of realistic intet on being a sailor see this thread if you have not already, Me and cranberrydavid have properly outlined the reality of this endevour -
http://squattheplanet.com/diy-die/squatting-alternative-housing/14047-sailboats.html#post104739
as for learning lingo and such see sailing anarchy.com they are about the closest to boat StP as I know of in existence. Plus if you want some water experience go to any harbor and talk to people ask them stupidly as it might sound to you and them if you can go sailing with them, more than likely if they don't wanna take you they can point you in the right direction, just don't tell them that you want to get a boat of your own that makes you sort of an enemy!