Before I got started down my current career path--that would be the information management/work flow/web strategy/technology and cultural analyst path--I worked in a library.
I suppose I should clarify somewhat as the image you have in your mind is almost certainly not accurate, both of what my library was like and of the kind of work I did.
I worked in a research library at the big local (private) university, and I worked not in the part of library where students went to get their books, but in the "overflow area" where the special collections, book preservation unit, and the catalogers all worked. What's more, the unit I worked with had an archival collection of film/media resources from a few documentary film makers/companies, so we didn't really have books either.
Nevertheless it was probably one of the most instructive experiences I've had. There are things about the way Archives work, particularly archives with difficult collections, that no one teaches you in those "how to use the library" and "welcome to library of congress/dewy decimal classification systems" lessons you get in grade school/college. The highlights?
Physical and Intellectual Organization While Archives keep track of, and organize all sorts of information about their collections, the organization of this material "on the shelf" doesn't always reflect this.
Space is a huge issue in archives, and as long as you have a record or "where" things are, there's a lot of incentive to store things in the way that will take up the least amount of space physically. Store photographs, separately from oversized maps, separately from file boxes, separately from video cassettes, separately from CDs (and so forth.)
"Series" and intellectual cataloging - This took me a long time to get my head around, but Archivists have a really great way of taking a step back and looking at the largest possible whole, and then creating an ad-hoc organization and categorization of this whole, so as to describe in maximum detail, and make finding particular things easier. Letters from a specific time period. Pictures from another era.
An acceptance that perfection can't be had. Perhaps this is a symptom of working with a collection that had only been archived for several years, or working with a collection that had been established with one large gift, rather than as a depository for a working collection. In any case, our goal--it seemed--was to take what we had and make it better: more accessible, more clearly described, easier to process later, rather than to make the whole thing absolutely perfect. It's a good way to think about organizational project.
In fact, a lot of what I did was to take files that the film producers had on their computers and make them useful. I copied disks off of old media, I took copies of files and (in many cases, manually) converted them to use-able file formats, I created index of digital holdings. Stuff like that. No books were harmed or affected in these projects, and yet, I think I was able to make a productive contribution to the project as a whole.
The interesting thing, I think, is that when I'm looking through my own files, and helping other people figure out how to manage all the information--data, really--they have, I find that it all boils down to the same sorts of problems that I worked with in the library: How to balance "work-spaces" with storage spaces. How to separate intellectual and physical organizations. How to create usable catalogs and indices's of a collection. How to lay everything down so that you can, without "hunting around" for a piece of paper lay your hands on everything in your collection in a few moments, and ultimately how to do this without spending very much energy on "upkeep."
Does it make me a dork that I find this all incredibly interesting and exciting?