I don't know where to book motel, but for hotel, expedia.ca is a good website to start with as it tells you all the local hotels and you can book it online with your credit card. I have used it for quite a while and had no problem with it. I feel that for Motel which is realtively cheap and small, you may have to call them to find out.
May not need credit card for reservation but they will only keep it for you till 4 o'clock. Go to CAA to get a travel book (old one should be fine) which contains lots of hotels and motels information.