Lincoln Stein (who wrote CGI.pm) wrote the "Official Guide to Programming with CGI.pm" (Wiley, 1998, ISBN 0471247448).

It is ( Well, "was at publication") comprehensive and coherent. No, it doesn't address modern templating modules, but the value of those will be dependant on the scope and scale of your needs.

As of this writing, Amazon, Abe Books, Half.com and eBay list used copies from US$1.07 up. Some of those offer a new copy at $40.00. It's certainly worth more than the lowest listed price (and to me -- though the edition is a decade old -- has been and continues to be worth more than the $30. I paid).

But, pray heed Cody Pendant's first point: Understand HTML, first, or the lack thereof will rise up and -- at best -- aggravate you greatly. To that, I would add, second: get at least a basic familiarity with CSS, as using styles will simplify your HTML (and often, make it more concise).