Hello P.,
First of all, thank you for purchasing any of my books.
Second, inner peace is not found in mantras, meditations, life philosophies or anything like that, but inside you. If you want to achieve peace of mind and emotional peace, just by not stressing, not getting angry and not worrying, you are well on your way. If you want to achieve spiritual ecstasy, nirvana, then live with love and you will achieve it.
Understand that the things of God are simple (even children understand them). Don't complicate your life.
Yes, my book "The Throat Chakra, the Development of your Life" deals with the throat chakra (it would be necessary).
I hope I've helped.
Hugs
Damián Alvarez at http://sistemasanaciontinerfe.blogspot.com/