I didn't say wxPerl was "better" than Perl/Tk... I said I
like it better. On most linux distributions, installation is as easy as "apt-get install wxperl". For windows, there are pre-built binaries available here:
http://www.wxperl.co.uk/
There are tools, like wxGlade, that make building your GUI a mostly drag-n-drop exercise. So, it is also possible to have a small app up and running in minutes with wxPerl.
The OP listed learning Perl/Tk as an essential step, as if it were the ONLY possible solution for GUIs with perl, and that's clearly not the case. There's also PerlQt. Like all things perl, TMTOWTDI.