As I recall from the video it is available from Amazon (the first outlet for it) on the evening of March 4 in e-format, and between March 6 and 9 in print.
Dykstra also said it will eventually be available from 40,000 outlets, within 2 to 8 weeks, in the U.S., Canada, Australia, Asia and Europe. It will also be in Universities and public libraries.
I have no idea about price but am keeping my fingers crossed that it will be reasonable.