Mobi CREATOR is for converting other formats (e.g. PDF) to a format that can be read on Kindle. When you do the conversion you have the opportunity to define the author and title so it shows up properly. It does not provide a way to edit this data in a book that has already been 'built' into a Kindle compatible format.
Mobi READER is a program you can use on your computer to read books created with Creator, if you wish.
mobi2mobi is 'perl scripts' (?) program that I really don't know any more about but that I understand to be something that you can use to edit the metadata (author/title/etc.) on a book already in the mobi/prc format.
To my knowledge -- which I admit is limited!

-- there is no way to edit such info on a book from amazon in it's native, DRM'd format.
Ann