Amazon is temporarily out of inventory, but CBD has it, as does WTS Books, and others (including me, see the various widgets running down the right sidebar).
This is a good problem to have! If you’ve not yet done so, consider checking out the book’s home page (which has been shared more times in two months than the Thriving at College page was shared in three years), reading an excerpt, watching the promo video, or reading a guest post I wrote for Desiring God or Bible Gateway.