Just hucking my $0.02 into the bucket here.
When I started I was 11, took a lesson every day for 3 days and I don't think I've had one since. It was a deal I got with school, bus, lift ticket, rental and lesson for $40 a day or something!?!
Anyway, fast forward 17 years and I got my GF into it a few seasons ago. Some hills have a combo where you get a beginner lift ticket, rental, and lesson for a really good price ($30-$90 depending on the resort). If they have this combo take advantage of it, because the full mountain lift ticket will be useless to you for the first day or two anyway.
So the GF did that combo for her first two days out. The lessons are very basic but you get all the practice time you need to start to feel the board under you. Since then she's taken a lesson every approx. 10 days on the slopes. She's been lucky enough to sign up for a 3 hr group lesson in her category (they're rated 1-5 our here) and get a fully private lesson for the same price! Think it was $75 or so with tax for those lessons...
But yeah, good luck and have fun! It's a great sport but day one will involve sore knees, ass and wrists... That's just the price of admission cause it quickly gets better from there. The learning curve is quite steep for the first few days and then generally speaking you'll be comfortable enough to explore all over the hill, heel sliding out of situations you're not comfortable with.