There's some good advice for you. I was waiting to the old "You have to take ASA 101 through 10bazzillion, crew for 30 years at yacht club, then buy a 3 foot dinghy for best feedback, and eventually buy a 40 footer." That's the elitist mentality. Hang around long enough, you'll see it. But these are some good words.
For my two sense, buy a trailer sailor, similar to what Jeff was saying. Easy on the budget and back. You can make all those mistakes and loose some gelcoat on an inexpensive boat plus you'll find out if sailing is for you. If you get one in the 22-25 foot range, weekend cruises are a great thing. We cruise for a week at a time in our Lancer 25. Then, you love it, learned a few things, so you sell the trailerable and move up to a 30 footer. Still not TOO expensive but more financial responsibility. The biggest thing is get experience. In the middle of a blow-down is the wrong time to open the book. When the sail tightens and creaks hard and it feels like a giant just grabbed your masthead, your hand should dump the main before your mind has a chance to think. That's experience. But . . . one more thing. Take a Sailing and Seamanship Course through your local USCGA. Knowing the rules on the water are paramount to safety. In Maine, certification is not required so most boaters are absolutely clueless but have "grown up around boats". Yeah, I grew up around horses but that doesn't make me a cowboy.