Now, I've just found out that the book that I've always wished were available is available! And it is free online, too. It was pointed out by Andrew Revkin in his NYT's Dot Earth post on which this blog was quoted yesterday, "Egypt, Inkblots, Agendas and Feeding 9 Billion."
Edited by Julian M. Alston, Bruce A. Babcock, and Philip G. Pardey
—From the Introduction and Overview
In this book we assemble a range of evidence from a range of sources with a view to developing an improved understanding of recent trends in agricultural productivity around the world. The fundamental purpose is to better understand the nature of the long-term growth in the supply of food and its principal determinants. We pursue this purpose from two perspectives. One is from a general interest in the world food situation in the long run. The other is from an interest in the implications of U.S. and global productivity patterns for U.S. agriculture.