LucidSW - 3:03 pm on Feb 9, 2012 (gmt 0)
Adwords changes all the time, at least the inner workings of it with small tweaks and fixes, like most software. The interface occasionally changes as well.
If you want to buy a book on the basics such as what button to push to add a keyword, which to push to pause it and that sort of thing, I think this is a waste. You can easily learn that by yourself just like most people do with any other software. How many actually open the user manual? Most simply figure things out.
There is no version number that I'm aware and any such book would always be out of date. Now, as you ask for advance techniques, which I take to mean not the interface but how to build profitable campaigns, there are fewer of those still. The basics of that will not change. True, Adwords has implemented new things in the past year. They always do and test many other things such as now tacking the first description line to the ad's title when displaying above the SERPs. It's not easy keeping ahead of these and sometimes, they are just tests and if not successful, never to be seen again.
I have written such a book. Rules here don't allow me posting links and this is self-promotion but check my profile for my site if you're interested. There are others of course. People talk a lot about Perry Marshall's book. I read his years ago, not sure what his latest said. There's also one by Brad Geddes (not sure of spelling) which I haven't read but others have mentioned is good.