School me in public parks camping...

I'm woefully embarrassed to admit that, after 10 years of camping, we have extraordinarily minimal experience with county/state/national parks. We've always done the 'rv park' thing. The kids are older now, however, and the activities and attractions of the commercial park doesn't have the same draw. So, I'd like to begin broadening our exposure. I am, however, utterly ignorant in the matter.

How do you find out what hookups they have and if they take reservations? Does any of this happen online, or is it all still a phone call? Is it realistic to look for parks with full hook-ups, or are those pretty few and far between? Where do I start when I know what area I want to hit? Is rvparkreviews good for these as well, or am I better off looking at other resources?

Don't shame me, it's just not been our bag to date, and I'd like to learn more. I don't even know what I don't know so, please, tell me!