This is one of those situations that's so achingly close to a win-win for everyone that it pains me. If only someone at O'Reilly could realize how close they are! Here's the problem and the solution.
Matt Neuburg's AppleScript book (not Neuberg!) is an excellent overview of AppleScript. Alas, it is limited, as all such books are, by AppleScript's peculiar nature.
The problem is that AppleScript is primarily useful when it interacts with scriptable Applications; this means that many important commands one may think of as belonging to AppleScript belong to Applications instead . If you working to extend an existing script, and decide to research a command in the excellent book index Matt built himself , you'll often be frustrated. The command, you see, belongs to the Application, not to AppleScript.
On the other hand, there's a good chance Matt used in the command in one or more examples. In the absence of a companion book entitled "AppleScript for Applications"  you'd like to find those examples. Alas, that's where you want a full text search engine.
The good news is, there are two. The even better news is that O'Reilly could make their engine much more visible and useful, with advantages for everyone.
Consider the case of the 'Duplicate' command, which is supported by iTunes (among others) and the Finder (in slightly different ways, no doubt). When I tried Amazon's "search within the book" I discovered several illuminating references. Similarly, O'Reilly allows one to search within the book as a promotion for its Safari eBook library: O'Reilly - Safari Books Online - 0596102119 - AppleScript: The Definitive Guide, 2nd Edition.
The Safari search works well, but they don't want to give away too much for free. You can only read a snippet of information in the search results. A snippet that doesn't, currently, include the page or section number. If you click further you get to the 'buy safari' screen, but you also get to see the section number. Now, you can return to the book and read the information.
Matt would love for O'Reilly to open up Safari a bit more, but they don't want to. That's ok, O'Reilly could make all of us (and themselves) happy by keeping Safari just as closed as it is today, but merely adding a section reference to the search results they freely expose already.
Here's the win-win for O'Reilly, Matt, book retailers and us:
1. Include the section reference in the initial search results screen.Let us count the wins:
2. Promote the search facility in every published O'Reilly book and explain how to use it on the O'Reilly book page.
3. If need be, request readers register to obtain this service. O'Reilly doesn't do spam, but they can suggest email subscriptions, RSS feeds, etc during the registration process.
1. Matt's book is suddenly a better book. Readers get more value from it. They use it more. They like it and O'Reilly more.It's a win-win for everyone. I just hope someone at O'Reilly can see the profit in it for them.
2. O'Reilly gets ongoing visits from its customers. Many would kill for this alone.
3. O'Reilly gets free, regular, promotion of Safari services.
4. O'Reilly sells more books, Amazon sells more books.
5. O'Reilly does not reduce the value of Safari, they enhance it by introducing users to it without giving it away.
 In my real life I'm a knowledge representation/informatics geek. I have a lot of respect for the unrecognized intellectual labor that goes into producing a truly excellent index. In this case Matt did the work himself!
 Many applications may use the same string to refer to somewhat similar functions with slightly different syntax and semantics. This "ontologic dilemma" is a kind of uncontrolled overloading, and it makes AppleScript very challenging to use.
 If Matt decides to sell an "AppleScript for Applications" as a Tidbits eBook I'll pay for mine in advance.