There is a bit of general marketing stuff about it here and there, but no actual info about where/how to buy it, what it costs, etc.
This page http://www.translationzone.com/products/multiterm-extract/ has some info, but clicking on Buy takes me here: http://www.translationzone.com/store/ (with zero info about the product)
Is it perhaps integrated in SDL Studio, or MultiTerm, and is that why I can't find it anywhere? Who knows? Not I ;-)
How about a nice link to a trial download, and a price?
Michael