Same as what Chet says about Everett's book and I don't have Kono's book yet…but…
I also have 'The Weightlifting Encyclopedia: A Guide to World Class Performance' which has some very high recommendations...including from Kono himself.
If you are quite new to Oly lifting/or just starting to train (which I am sort of <2 years) then Everett's book is what I would suggest because as an introduction it has some good instruction and it is quite easy to follow, lots of pics (great if youre a visual person), that takes you through the lifts and assistance lifts and supplementary exercises. I know there have been some critics, but my knowlede is such I can't really pick at it.
If you are just starting out and if you work better with visuals, I would not recommend the WL Encyclopedia to learn from (unless you like to read a lot). I bought it 3 years ago I think when I was just starting to find out about oly lifting. I thought wow, lots of pages, high recommendations must be good. When it arrived, I thought, WTF. Where do I even start to read this thing.
Not knowing as much about the lifts back then so I found it very hard to get my head around the volume of text…there is lots of it…over 500 pages. The detail in this book to be honest just couldnt hold my attention back when what I wanted was some simple to follow introduction with sequential pictures, like Everetts book.
NOW, HOWEVER, with my interest in this type of lifting having grown, I am just starting to appreciate that WLE is quite an amazing book and superior to Everetts book in the amount of knowledge that is in it. It is immense. It covers all possible aspects of training Oly lifting from what I can gather. In depth detail of content can be found here:
http://www.wlinfo.com/ with excerpts from different chapters shown to give you an idea.
Everetts book is good and recommended, but it you really want in depth insight and something that will always add to your knowledge both as an aathlete and coach, then WLE should be considered if you want to spend those hard earned notes. I paid quite a lot for it…cant remember how much, about £40-50 plus delivery.