Librarianship is a horrible profession to be in if you want to have a family; jobs are insecure and low-paying, you have to be very mobile, you won't be able to live in a neighborhood with a good school, and you'll have to train your child for a career someplace besides a library as there will be very few librarians in 20 years. I'll probably be single forever so I'm happy to be a librarian.
I've been curious about what would make me qualified for a administrative job. I'm pretty good at my own job as a reference librarian, but a lot of the ads I see want several years of supervisory experience to be a head of reference, experience which I can't get except as a head of reference. I think I'd make a good one and so do some other people, but without already doing the job i'm not qualified to do the job.
Anon @ 7:38, Librarian positions are indeed not low paying for everyone. However, compared to some other professions requiring advanced degrees, librarians aren't that well paid. It's lovely that you don't want to make much money and aren't motivated by materialism. The field of librarianship wants more people like you.
And Steve, sorry to be so discouraging. But look at the bright side, it took years of being a librarian before I got this annoyed. You, too, can have several years of bliss in your chosen profession. And maybe I'm just a crank who doesn't know what I'm talking about, in which case you can ignore me.