I've actually given some thought to joining a rifle club or something along those lines. Trouble is, I know absolutely nothing about guns (I've shot an M-16 ONCE in boot camp, and that's the extent of my experience), and don't have the money for one right now. Still, you're right that most likely there'd be a lot more guys than gals at such doin's, and most of them would be conservative.
Though...locally it seems like mostly the older guys are in clubs. Younger guys just hunt...every season, every type of weapon allowed, all through fall and winter. ;-) During most of November and December where I used to work, there wouldn't be more than a handful of guys at work on any given day. And where my brother works, they get the first Monday of hunting season off, by default. We take hunting seriously around here!
There inexpensive NRA sanctioned clinics that will teach you all that you need to know, and believe it or not, you can buy used service rifles from the government at a really great price. You should not need a rifle to get started. Most clinics have rifles for shooters wihtout them. Give the NRA a call and start asking questions.
As for there being mostly older guys, yes there are a lot of older guys. But there are also lots of younger unattached ones, too.