Reddit mentions of Right Concentration: A Practical Guide to the Jhanas

With Each and Every Breath by Thanissaro Bhikkhu
Mindfulness, Bliss, and Beyond by Ajahn Brahm
Right Concentration: A Practical Guide to the Jhanas by Leigh Brasington
Wisdom Wide and Deep by Shaila Catherine
Mindfulness in Plain English by Bhante Gunaratana
Beyond Mindfulness in Plain English by Bhante Gunaratana

Practice and having the right conditions/setting/environment. Check out Leigh Brasington's new book, "Right Concentration," which gives very practical advice for working through all eight jhanas. Time and patience are extremely important. These states are easier to achieve on retreat setting, so you might consider planning a lengthy-ish retreat if you are able to, giving yourself plenty of time to explore the territory.

I have not progressed further than the above, but Leigh did release a book on how to progress to the others this year. It's called Right Concentration.

Right Concentration is an easy recommendation. Here's more of Leigh's content here.