The narrator of the Lord of the Rings is never a character in its own right (though we do hear a lot of stories from the different characters' perspectives within dialogue). However, we think this third person perspective is a little odd. Much of the material of the Lord of the Rings is supposed to come from the Red Book of Westmarch, written by both Bilbo and Frodo themselves. So why isn't the Lord of the Rings series told from the perspective of Frodo and/or Bilbo? Well, doing so would really have changed the tone of the book, and it would have been hard to keep going once Frodo and Sam and the Fellowship go their separate ways at the end of The Fellowship of the Ring. We can see why Tolkien opted for the more neutral third person perspective.