Amazon has a copy for $29.99 new (sometimes you find titles for even less)- and occasionally if you watch them, you'll find the odd used one posted for sale there. However, you do also run into some people that have strange ideas about worth (in other words there seems to be a few folks who think just because something isn't listed on Amazon - it is oop -and it leads to insane price requests like some guy wanting like over $100 for Wagram (or it might be Eckmuhl).
And if you buy these things through the link on SDC (in this case:
http://astore.amazon.com/scendesicent-2 ... 131&page=2 ) for Atlanta - then the site gets a commission on the sale (while the price for, you the buyer, is exactly the same).
You'd be surprised what pops up there.
[Edited to add the disclaimer] -Amazon rules for shipping software applies -so the software material (check with Amazon about where they ship what product types to), I don't think they ship outside of North America on that sort of things -while books and videos seems like there aren't any limits.
Edit part 2: Also if anyone decides to sell anything there, feel free to drop me a line, and I will be happy to ensure it has a prime spot in the SDC shop.
Edit Part 3: Another example - someone was flogging a copy of Mexican-American War there (saw it there yesterday at least) -- $19.99 (I presume it was used) - but they can be there on Amazon as well... just a heads up.