Canadian citizens using a Canadian passport now buy a visa-on-arrival visa-on-entry in Zimbabwe. Canadians do not get a visa prior to travel to Zimbabwe according to both the government of Zimbabwe and the Embassy of Zimbabwe in Ottawa.
Canadian citizens cannot use e-visas. Just fly or drive to Zimbabwe and buy your category-B "visa-on-entry" at the airport or border entry point for US$30 (single-entry); US$45 (double-entry); or US$55 (multi-entry with letter).
Click here for more details on who can get a Visa-On-Arrival in Zimbabwe; who is visa-free; and who needs to apply for the e-Visa.