Your experience with wxPerl seems to be different than the one that I have had. In the year that I've been using it I've found it to be much better documented and easier to use the Tk.

All the objects and methods map 1:1 to the C++ API documented here, and anything that is different in wxPerl is noted in that same document. You can also install Wx::Demo from CPAN, which is a demo script that shows you how to use all of the widgets.

Up-to-date PPMs for ActiveState on Windows are available here. I also had no problem building the module with CPAN on Debian.

I haven't yet run into any classes missing from the perl port that I've wanted to use (although Wx is a huge library and I certainly haven't tried all of it.) In general, everything just works more consistently and looks better than in Tk. I had a lot of problems trying to inherit from Tk classes -- in WxPerl you just use base 'Wx::Whatever' and it works how you would expect.

It would definitely be worth your while to take another look at wxPerl. Although the API is a little less Perlish than Tk's, it is generally cleaner and more consistent, and the resulting GUI is much more attractive.

edit: I just re-read your post and noticed that you were concerned about using the C++ API reference instead of a dedicated Perl document. Essentially the only difference between the two would be changing the class names from wxWhatever to Wx::Whatever and changing the name of constructors to new, so maintaining a separate document would be a waste of effort (and a pain to keep in sync as the main Wx documentation evolves)