Another good way to get the books in people's hands, for mods that aren't early-game focused, is to have them as quite common drops in loot chests, and guaranteed in the starting chest if you play with the starting chest option on. Thaumcraft has them in loot chests at totems, which both makes sense and is a great way for new players to learn about the mod "when the time is right".
Of course that's of limited use in multiplayer where everything gets looted quickly, but in multiplayer you have people to ask.
Of course that's of limited use in multiplayer where everything gets looted quickly, but in multiplayer you have people to ask.