I read this novel more than 30 years ago.
It begins with a (orphaned ?) little girl who lives in the streets finding a weird book. It talks, and is probably AI. IIRC, it is one extra illegal copy of a very restricted set meant for daughters of extremely rich people. Since no legal copy is missing, it is not generally known it exists. So the life of that girl is changed in an extraordinary way. This is only one thread in the very complicated plot of that novel, but I don't remember anything else.