I agree with the whole classes thing, and as many books as you can fathom (pun intended).
Heres another option.
I'll make the assumption that there is a yacht or sailing club at the the marina.
Wander in early on a Saturday morning with lots of coffee and doughnuts.
Tell some of the people there of your plight/opportunity.
We're an opinionated bunch, but I have yet to see anyone refuse a sail on another persons tub, if they have the time. (inducements of refereshments and food are always welcome)
It will take time and practice to learn how to dock, this may be one of your most important lessons, we all get a little hinky when a "new guy" is bringing his boat in for the first couple of decades
We are not primarily on earth to see through one another, but to see one another through
Some people are like slinkies: not really good for anything... but you can't help laughing when you push them down the stairs