Yacht club might be a good option -- on the Susquehanna the two public launches are insanely busy on a sunny Saturday. Drunk powerboaters with little tolerance for sailboats. One of the launches has power lines right over it which leaves me with only one two-ramp launch to use. There is no overhead obstruction between the parking area and the ramps so I can take my time rigging it in my parking spot.
There are lots of great books - there's a thread on here discussing favorites. Even a trip to Border's will turn up some really good ones. (Join their rewards club first - they send you a 30% off coupon every week or so)
My friends repeat the "hole in the water" line but the smaller the hole the less money you have to dump in it. And for some reason I never seem to mind improving my boat. If you're living paycheck to paycheck then buying a boat maybe isn't for you, but if you've got a little budget set aside for a hobby (a FAMILY hobby!) then have fun!
My other interest is old German cars and there's a saying there that applies here too. "There's nothing more expensive than a cheap Mercedes" It seems for the most part, it applies to boats too. A $1000 Catalina 22 might need $5000 of work to become a $2500 boat. Whereas a $4000 boat might need nothing more than a coat of wax. And if sailing isn't for you - you can sell it for what you paid. The trick is to find a $4000 boat for $1000.
Selection might be a bit slim right now, but prices are great. If someone is selling a sailboat in February it's because they need money quick! Once sailing season gets close, more people will be selling their boats because they've bought a different one.
Get a list of what equipment comes with a boat. Dock lines, fenders, life vests, boat hook, anchor, compass, porta-potti. that stuff isn't a fortune but it will add up. I found a fish finder / depth finder / GPS at Dick's sporting goods for $150. It's a little screen and it's only black and white, but it's been wonderful being able to see how fast I'm going, and where I am. The speed feature is nice -- you can see what sail trim adjustments do to your speed. Depth finder is great too if you sail in shallow areas. That's another thing about retractable keel trailer boats -- if you hit bottom just crank the keel up and back 'er off. And you can crank it the whole way up and run it right up to an island to explore. Just watch the tides or you'll be there for a while. Dig for clams, whatever!
There's some great people on this forum - and there's a section for "boat purchasing" or something like that. Post the craigslist ad and get some opinions -- if nothing else, you'll learn what to look for.
And take a friend with you when you look at a boat. A second set of eyes might catch a sloppy hull repair or a fraying stay while you're thinking about sipping margaritas in the Florida keys on your new dreamboat. Wives are good at this.