I've recently discovered Duotrope's Digest of Fiction Fields, an excellent (and currently free) source of information on paying fiction markets.
Now that I've had a little time to explore the Duotrope site, and have determined that it's pretty thorough (and unbeatably timely) with its information, I can't really see a good reason to keep selling our own e-book guide to paying short story markets. So as of today, that e-book (just updated last month) is going to be available at no charge here.
I hope you find it helpful--I think it does include at least a few markets you still won't find at Duotrope. And if I ever feel there's a real need for our e-book to come back in a new life, I will let you know!