Re: Lucid Dreaming, Skrying & Projection
The studying of some of the Theosophists and Rosicrucians can be very insightful, depending on who it is(some of them are black magicians who are awakened negatively).
There's alot of garbage out there though; in all fields of spirituality.
There's quite a bit of stuff that's very marvelous as well.
The Inner Master is the one who distinguishes of course, not the ego.
You're right about reading about Astral travel though, considering that it's more of an emotional thing.
Nonetheless, the books I suggest are probably the best ones out there; if one wants to know the exercises related to Dream Yoga.