Exactly what are you trying to do. My understanding is that our windows and windshield are already coated cut down the UV Light.
The following link may apply to the US, but then I am sure that apply to Canada as well. http://answers.yahoo.com/question/index?qid=20100717134724AAgcUxF
I have all my glasses except windshield tinted for "additional" protection, it is nice during summer time because the average temp inside the cabin is much lower.
Of course, the front windows cannot be tinted in BC, and if caught, you could be fined.
I used NMotion to do my tinting because they are the sponsor for my forum, and gave me discounts. Their work is still good even my car is almost 10 years old. I would recommend them.
Currently, I am doing 20% front and 80% rear to make sure the cops won't see them.