It's hard to do Jewish genealogy and not run into Avotaynu, the long-time and as far as I can tell only publisher dedicated to publishing books on the topic of Jewish genealogy. They also publish a self-titled quarterly journal, Avotaynu, on Jewish genealogy and an e-mail newsletter called Nu, What's New?.
In this weeks' Nu, What's New? e-mail, Avotaynu mentions that while the set costs $199 on Amazon, they are currently selling it for only $99 plus shipping, per arrangement with the publisher. Shipping from Avotaynu is $20 in the US. So $119 for the books plus shipping.
NYU Press, the publisher, is also selling it for $99 plus shipping on their own site, with the use of a coupon code (see their site for the code). Oddly they show the $99 price as a discount from $350, yet if you go to the regular page for the set, it sells for $199. In any event, it's currently $99 plus shipping. I don't know what the shipping costs are from NYU Press, as you need to become a member of their site to find out.
Interestingly enough, Yad Vashem also sells this set directly from their web site. However, Yad Vashem sells it for only $55. Shipping within Israel is free from Yad Vashem, so if you live in Israel it would seem to be a no-brainer where to order it from. If you live outside of Israel, shipping costs $55 which while high, still brings the total cost in the US to $110 instead of the $119 from Avotaynu.
In short, if you live in Israel, definitely order it from Yad Vashem directly. If you live in the US, perhaps check out how much NYU Press is charging for shipping before deciding where to order from. I highly recommend this set for anyone researching their family in Europe.