I agree with Arun. Johari's books, IMO, are very good introduction. Beside "Tools for Tantra" also see his book "Chakras" and just about anything else by him. I would also suggest some of the works by Dr. John Mumford such as "The Tantra and Kundalini Workbook." You can also find on the internet book(lets) by Sri Mahendranath Maharaj that include ritual and techniques. Books by Michael Magee have information on the Sri Yantra. There are a few books on the subject, but some are very hard to find such as those by Ramachandran, Rao, and Shakaranarayanan.

There are, indeed, some people who will tell you that you can't learn from books. In fact, a few have criticized me because I dare to have some small knowledge of books on the subject of Tantra. IMO, the truth is that you can't learn "everything about Tantra" from books. Indeed, you do need to have an experienced teachers. However, IMO books can expand what you learn from teachers. I believe that both in-person teachers and book studies are valuable. Either by itself is incomplete.

Namaste!