> Perl does have good documentation provided by O'Reilly in the form the
> llama and camel books.

Perhaps you've noticed, perhaps not. The Camel book is essentially a printed version of the perlfunc perldoc/manpage. Which means in particular that the exec function is just as obscurely documented for £26.80 as for the free machine readable version.

As to the state of the documentation, you should be aware that the evolution of perl over the past two or three years (since 5.003) has been in great leaps and bounds, with the number of modules in the CPAN more or less keeping pace. The amount of documentation is awe inspiring, if some of the individual examples of it perhaps are not.

Now that 5.6 is out, give the documentation a year or so to catch up.

In the meantime, sites like this one can fill the gap, at least in terms of pointing out which of the hundreds of "things" to read might be helpful apropos of a particular problem.