As mentionned, the whole story behind is that teh book is out of print and very difficult to find. Furthermore, it is more or less the ONLY book compiling information about Catasetum (and includes most species currently valid).
I have the book and I love it! However, I can also say that if you are not really into Catasetum it is not worth to spend that much money in the book.. but if you are into Catasetum, just go for it!!
Check in Amazon, sometiems you can get it cheaper there (used). My book came last year from Amazon and was only 120$ (shipment to Europe included!). I have seen twice or thrice there with price variations since then...