Accommodations in Canada vary substantially in price depending on time and place. In most cities and many tourist areas, expect to pay upwards of $100 or more for a good hotel room.
In rural areas, motels (for "motor hotel") are small, simple hotels where you might pay as little as $40 for a night's accommodation (especially in the off season.) In many areas, a B&B (bed and breakfast) is a nice option. These are normally people's homes with suites for guests. The price - anywhere from $45 a night to $140 a night - usually includes a breakfast of some kind in the morning.
Other options include cottage rentals on the lakes and in the countryside and apartment rentals in the cities. Prices compare to hotels and motels and this type of lodging provides some comfort of home while you are traveling.
Youth hostels are a good choice, offering lodging in shared dorms or private rooms for $15 - $40 per night. Some useful resources are Hostelling International Canada, Backpackers Hostels Canada, and Pacific Hostel Network (which also covers Alaska and the Northwestern United States). Most hostels in Canada meet very high standards.
Finally, there is a huge number of campgrounds in Canada. These range from privately owned R.V. parks to the publicly operated campgrounds in national and provincial parks, and are almost always well-kept and generally very beautiful.