A four-day advanced Perl & Perl/Tk course in London costs £2000 where this book was £40 - including CD from which I installed Perl and Perl/Tk on my Wintel box.
Wanting to learn Perl I grabbed the first book I found at the local bookshop, yet I can't imagine how the choice could have been more fortuitious.
If you're put off by the comments in other reviews about the index, bear in mind there's an HTML copy of the book (so useful!) on the CD as well as an enhanced index.
This book covers Perl syntax (1st half) Objects (2nd half) and practice/debugging (1/3rd half - how's that for value?). As a C programmer I was virtually able to read it straight through - the highest tribute I could make both to Perl (it just makes sense!) and to this book.
Little things like the CGI options checker script, the Calendar Tk App (filling the one hole, I think, in windows) and the nod to a well-known book on algorithms made me have to acknowledge this book's breadth. And it is likable too. You don't feel the author is ever talking down to you, yet the sheer scope of info makes this book entirely valid as a bible - alongside even Programming Perl.
And no, I don't know the author. This is actually genuine. I haven't seen it recommended in the newsgroups and I thought it deserved better!