At long last, the fourth edition of the Math Guide is available for purchase at Amazon.com, Google Play, and this site (although I’m struggling a bit to keep inventory in stock on this site, so please be patient if you buy directly from me). It will eventually be available at other online locations (e.g., B&N) too.
A lot of other folks rushed to publish books for the new SAT to take advantage of the uncertainty and panic that a new test brings. I didn’t do that. I really took my time on this one to try to get it right. Once you have a look at it, I hope you agree that I did a good job.