The main Web page for readers and contributors to tkinter-discuss is https://mail.python.org/mailman/listinfo/tkinter-discuss .
The mailing list was launched in the USA, on 16 March 2004.
Its charter is to host all discussions related to Tkinter, including help in use of Tkinter, and the module's maintenance and enhancement.
Why a mailing list, rather than disciplined use of "Tkinter" in subject lines of postings to comp.lang.python, for example? As charter subscriber Kenneth MacDonald noted early on, "I find that a mailing list is better if I have a particular focus."
Archives of the list are located at https://mail.python.org/pipermail/tkinter-discuss/ and GMANE http://news.gmane.org/gmane.comp.python.tkinter.