I have a book case, but I also fill up the spare gaps in my TV unit with stacked books, and have little stacks of vintage ones all over the house. I also have a small ladder (five rungs) that I've leaned against a wall and stacked books on. It looks very cute, and holds a surprisingly large amount.
It cost little really, and it is very very thin.What is great, that only about 35 books can be stored.It has a door, so they don't look messy, some are not the best looking.
Makes sense, because any more and well they just collect dust.
I think one needs to be sensible, ''books in moderation''.You can always get more! Once you have read them.
I like my books to stand upright on display. So I have set up one wall in our study for this. One entire wall has ceiling to floor book shelves! You can get someone to make wall shelves for you or get them from ikea. My father has a proper library in his house. It's actually set up as a library so you can walk in between shelves choosing books. That's what I wanted but I don't have a book collection such as my father's yet:)
As I'm constantly collecting more books with numerous discounted sales during the year, I made some space in a shelf of the tv unit and on a shelf upstairs in the bedroom, where I put the smaller paperbacks.
Once read (or returned from my mother after she's read them) I pack them away in a box in the garage, with a list on with the titles. Easier to manage that way as I have limited space.