I would like to see some "real-life" samples on how to write the code, starting with a simple piece of a program and then expand from there. If I can see what I am supposed to be doing (eg changing the layer of an entity), and how that fits in to how I work, and then how it could benefit me, I would be more likely to buy a book. (especially if it doesnt get too technical too quickly)
Also the book would benefit by having "reference" section to make it so it is still useful to me once I have learned how to do the samples provided.
Any coding book in the UK sells for approx £20 to £30 whicjh I suppose is up to $50(ish) dollars(US)