1) I have heard that the philokalia, gerontikon, and unseen warfare are useful. Can someone point me to a good version of these on amazon? I don't know enough about what they are to know what to buy.
2) I have 3 books that seem to be a translation of unseen warfare, but I can't figure out which is first, second, third.
3) On the ladder of divine ascent, I feel like I am getting in over my head after the first few chapters. I have assumed that the 30 steps in the ladder are somewhat sequential, so there is no benefit to read about later steps when I am still trying to work on the early steps. But I just wanted to be sure that is true.