I had to take only one exam for the ATP; it was twenty-five questions. This is the prep I used:
PilotTraining.ca > Ground School Courses
You need no endorsement, and no flying is required. You will need an IPC within the last twelve months preceding your application. I elected to pick up a Canadian RRTO as well, but that is not a prerequisite for the license exam. Do have a passport picture (cut to Canadian specs) available; a Canadian Costco did this for me.
You'll have to appear at a TC office to take the exam, of course, and can contact the office of your choice to ask questions. The cost was $100.00 plus $30.00 per type rating. They take credit cards.
It's so easy to get I couldn't pass up the chance and it may be useful in the future, but in truth I have no immediate need. Is there some advantage in having a TC license at your place of employment?