For phrase, "For book owners."


Is it right to say "本の持ち主のために。" or "本の所有者のために。"?

I'm envisaging a situation where someone has done a simplified version of
their book on the internet and it says "For book owners, see page 115 for more
details".




Your translation is _not_ correct. In this caser, we never say 〜のために**.
Instead of it, this is correct:

> 本の所有者/持ち主の方(へ)

But in this case, we use **polite** words. So I would say:

>   * 本をお持ちの皆様、(詳しくは)115ページをご覧ください
>

お持ち and ご覧ください is polite form (尊敬語).

