Oh sweet. I didn't expect you to get to that so fast.
If you decide to do it, that's an e-book I'd definitely buy.
I'm working on a tile RPG right now. I've got tile movement down. I've got line of sight working. I've got collision working. Right now I am trying to figure out a good way to handle all the data involved.
As an example, a terrain tile might be "rough terrain" and a "hurt tile" and a "light blocker" - and it might generate a special sound when it's stepped on. Those four elements alone generate a lot of data to manage (and I'm using more than for). That is what I'm working with now.
Next I will have to tackle how to handle menus, choosing dialogue, dragging and dropping weapons, etc. Anytime there is a guide or book I can read through I check it out.
