The easiest way of gaining mastery over the Tcl Tk programming language is by referring to and learning from the highly-recommended Tcl Tk books. Let’s take you over couple of important book titles that are a must for anyone wanting to master Tcl Tk:

Practical Programming in Tcl and Tk (Fourth Edition) - by Brent Welch and Ken Jones

This book on Tcl Tk programming is apt for all courses related to Tcl Tk scripting, and various courses related to UNIX shell scripting. In its fourth edition, Practical Programming in Tcl Tk serves as a definitive guide for all prospective Tcl Tk developers of various levels ranging from the seasoned Python and Perl programmers who wish to effectively use Tk for creation of optimum quality cross-platform user interfaces, to absolutely new developers.

The book has been updated for the version 8.4 of Tcl Tk and it brings together authoritative and comprehensive coverage of all Tcl Tk commands included in the core toolkits as well as detailed examples demonstrating the best ways of using the Tcl Tk tool kit. The extensive coverage of Tcl Tk 8.4 provided in this book includes:
– labelframe, panedwindow, spinbox and other latest widgets
– Improved internationalisation support and
– The Tcl Tk VFS (Virtual file system)

The book caters to all developers of Macintosh, Windows and UNIX environments. Apart from many other things, the readers are also provided with instructions related to web application development using the TclHttpd web server. There’s a CD-ROM which consists of all the sample codes featured in the book, the latest Tcl Tk binary distributions, a comprehensive collection of various Tcl Tk freeware and TCL extensions.

Tcl Tk - A Developer’s Guide (Third Edition) - by Clif Flynt

This is another very heavily recommended book for existing as well as prospective Tcl Tk developers. It’s a newly updated edition consisting of over 150 pages of the latest TCL extensions’ related material. The readers are taken through the basics first and are then introduced to the various tools that make Tcl Tk the Swiss Army knife of the programming languages. You get to learn everything that makes Tcl Tk the ideal choice for extending applications’ capabilities and enhancing the programs, enabling you to become a better programmer.

The updated edition of this book throws light on all the latest features of Tcl Tk version 8.6, including the virtual events, team widgets, existing data structure implementations, creation of mega widgets and object-oriented programming. Online tutorials and an extensive collection of code snippets in various languages provide the readers with a firm grasp over the Tcl Tk libraries and the Tcl Tk interpreters.

All in all you get to learn the best strategies of using Tcl Tk to your advantage.