The most concise teachings describing the eight factor of the noble eightfold path, with the detailed descriptions of jhanas (based on the suttas and—without doubt—on deep personal experiences) by Ajahn Brahm are available in the following book: “Mindfulness, Bliss and Beyond—A Meditator’s Handbook” (also known as “Happiness Through Meditation”).
The preview (full ToC and chapter one) is available here:
The first part of the book describes the prerequisites for the deep states of calm, that culminate in the stillness of jhanas, and is targeted to all meditators.
In the second part titled “To Bliss and Beyond” Ajahn Brahm goes into great detail on what jhanas are, how one achieves them and what their final purpose is.
There are also numerous meditation retreats, where Ajahn Brahm teaches according to the topics described in the book, and they are all available right here 
If you are interested in more sutta readings by Ajahn Brahm and other members of the BSWA dual sangha, they are also available right here: