I got that postcard too. IMO your $129 would be better spent on John Siegentalar's, Modern Hydronic Heating: For Residential and Light Commercial Buildings" Amazon sells it for $225.56 That's a lot of money for a book but it's now in it's third edition, so that tells you something. It's not a cookbook, but teaches you physics principles applied to hydronic heating. Highly recommended to someone that wants to really understand things. Just look at the used prices for the earlier editions of this book. Unreal. Far more than I payed for my 2nd edition new.