I agree that the documentation is pretty sparse which is why I ported the wxBook examples, see the GitHub reference above. I use the pdf document "wxWidgets 2.8.10: A Portable C++ and Python GUI Toolkit" by Julian Smart, Robert Roebling, Vadim Zeitlin, Robin Dunn, et al February 2009. It's for C++ with wxPerl and Python notes sprinkled in where the usage varies. The 2381 pages is a lot to digest, but it does get easier to use as you get the hang of how things translate. Most of what I have found so far demonstrates individual widget usage. I am having trouble finding examples of a more complete application. I understand that this may be difficult as real applications will probably contain modules that any given user may not have installed.
There has been a lot of recent discussion on the mailing list - firstname.lastname@example.org - about writing a wxPerlBook to parallel the wxBook. This is also a good place to post questions. There is also some activity on StackOverflow.
There is a new resource you should check out that collects several resources together - http://www.wxperl.it.
Then there's always http://www.wxwidgets.org
, but these also have the problem of being C++ documentation which will require interpretation.
There's never enough time to do it right, but always enough time to do it over...