http://www.perlmonks.org?node_id=153814

Item Description: A guide to everything Tk

Review Synopsis:

I was impressed with this book fom the moment I opened it sitting in the bath-, er, reading room. I've been using Perl/Tk for at least 5 years, and I used Tcl/Tk before that. I consider myself almost an expert in it. Having said that, I learned five new things in my first five minutes of reading, just by flipping through the book.
Mastering Perl/Tk illuminates every dusty corner of Tk, without seeming to get bogged down in the details. It covers all the little things you might never find on your own. Changing cursors, balloon help, palettes, listbox virtual events, canvases as postscript, pie menus, animation, the adjustor, and more. At the same time it provides full coverage of the important widgets- lists, canvases, text, etc.
It covers the main loop in detail, ipc with the send command, and the options database.
It also shows how to make your own widgets, both in perl and c.
In short, it covers everything. Buy it. The Emu book will become the Camel book of Tk, the standard reference for the toolkit.
And finally, hats off to O'Reilly for the look and feel of this book. I don't know what it is that they changed, but the typesetting in Mastering Perl/Tk seems cleaner and crisper than in earlier O'Reilly titles; it's very easy on the eyes.

pete