Most of these books I've actually read and dealt with.
Again in my point of you there is nothing like the SDK
And now for the books:
Working with Microsoft Dynamics CRM 2011 (Developer Reference)
Microsoft Dynamics CRM 2011 Unleashed
One thing I have learned about CRM since I began using it is it has a million different features with a million different uses. It is a great program but only if you know how to use it. Microsoft Dynamics CRM 2011 Unleashed explains every detail of Dyanmics CRM 2011 in a way that is easy to understand. I keep this book at my desk in case there is a feature I would like to know more about or if I want to know if Dynamics CRM is capable of something. Great book for reference.
Microsoft Dynamics CRM 2011 Administration Bible
Once you purchase this book and it arrives you'll know why the title of this review says that this is the CRM 2011 book to own. This is not your 'average' CRM book. First, the book contains more than 700 pages of CRM vital information. It takes the reader from "Laying a Solid Foundation" through "Extending and Integrating". What's in between those two, nothing but pure CRM goodness; architecting the application, installing, managing data, Sales, Marketing & Service, working with Entities, Processes and more
Microsoft Dynamics CRM 2011 Application Design
I thoroughly enjoyed reading the book. This is the only book in the market that talks about and teaches how to design solution using Microsoft Dynamics CRM 2011's various customization and extension features. This makes the book helpful to both readers who are new to CRM as well as experienced. There are total 8 chapters in the book in which readers will learn the basics of CRM 2011 and will also learn how to implement and create applications like Project Training Enrolment System, Employee Recruitment Management System, Hotel Management System etc. using CRM 2011. The readers will also get to learn how to create Silverlight applications, ASP.NET pages which integrates with CRM 2011.
A must read book for any serious CRM developer.