You are asking a lot of questions here that you should be asking those colleges.
1. Ask the colleges if they have surveys of how many of their graduates find jobs and how fast and how much they make. Many colleges do update studies of their graduates to get this information to provide to potential students.
2. Ask these colleges if they provide internship and placement or any assistance finding a job. Many colleges have their own job board, employers will come to them and ask for fresh graduates and the college will provide the information to the students to apply. I think it's uncommon that they will actually find a job for you and place you there.
3. You can read about post-grad work permits here:
http://www.cic.gc.ca/english/study/work-postgrad-who.asp You can not get a 3 year work permit unless you study for 2 years or more. If you study for 9 months, you get a 9 month work permit. You will have the option when you find an employer to try to get a labour market opinion and change your post-grad work permit to a regular work permit which is extendable.
4. What is your question?
5. Different colleges may call their courses a diploma or a program. I don't think there is any fixed definition of the difference. Diploma is usually a shorter course that doesn't end with a degree but a diploma that says you learned this or that.
6. Again, you need to ask these colleges if they will pick you up from the airport and give you free trial housing. Unless you are disabled, I do not see why you can not find a bus, train or taxi to take you from the airport. That is what most people would do. Most colleges would not offer you free housing. Some colleges offer dorms where you can live or they offer you assistance to find a room or apartment but you would have to pay.