If you are using the installer, I think I'm not sure if you should see a folder inside the wx main folder called doc , otherwise, just google 'wxruby' and the name of the class or object you want to know
For instance:
File: /// C: /Ruby193/lib/ruby/gems/1.9.1/gems/wxruby-ruby19-2.0.1-x86-mingw32/doc/auimanager.html
As you can see, the url is my hard drive. I'm not sure where to direct you, but this is the most useful resource that I have found yet, I'm not sure about the more complex widget controls, but I'm sure wx not the best GUI there is.
If you want, I would not want to send you email, there are several hundred html documents of very useful information about this
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