In order to stay in Mexico for a long period of time Canadian residents do need to access either a visa or tourist card in order to stay there legally. There is a certain regime you need to go through in order to find the correct paperwork and obtain the right information you need. Firstly you should attempt to visit your local Mexican embassy and make a request for a tourist card. However, if this option is not the most feasible to you then you could access any Mexican tourism office and ask them for tourist card. Moreover, you could also visit a border-zone airport as well as the border crossing point into Mexico for the right information.
What will you need to have when you get there?
Once you have gone to the embassy, tourism office, airport or crossing border then you must show them an official form of identification. This can include a valid driver's license, passport or birth certificate. Once you're there you will have to fill out all the appropriate forms they give you, however make sure you fill them out carefully because any mistakes may prevent you from securing a card.
The tourist card is valid for up to 180 days so you should decide how long you want to stay in Mexico for. In some cases, people validate their card up to the full capacity even if they are planning on leaving earlier because then you won't have to apply for an extension if you decide to stay longer. However, if you are completely sure that you will only be in the country for a specific amount of time then you can lower the validity of the card.
No you do not. If you're flying to Mexico the airline will issue you a tourist card, and charge you a small fee - used to be $23 but I don't know what it is at this time. You will need to show proof of citizenship or permanent residence in Canada and a birth certificate, driver's license or photo ID. And you will need your permanent resident card to re-enter Canada.
If you are going for a short visit, like a day trip, you need a passport, just like anyone crossing an international border. If you are planning a longer stay, like to live there or go to school, then you will need to visa.