The OGS has put on their website every municipality in Ontario (city, town, village, township, regional municipality) and all of the geographic townships which have belonged to a municipality.
Current and historical townships are on the website, but not the unorganized townships.
At a future date the list will be expanded to include the former Police Villages and the current hamlets.
If you are researching historical land records, the "Ontario Locator" can be used to this purpose.
You can go to http://www.ogs.on.ca/ontario_locator.php?name=5