I am also pursuing an idea, I emailed an attorney and this is what he said: probably similar in Canada and the US
In order to get a patent, your idea needs to meet three criteria - it has to be new, it has to be useful and it has to be non-obvious (basically, clever or inventive). The flippant answer to "useful" is "if it isn't useful, you won't sell any", but it does require that the invention perform a function. "New" and "non-obvious" can be assessed by doing a search - the US and Canadian patent offices have made their patent databases publicly available for searching on their webpages which you can find in our links section. When searching, if you find a related invention (one that is solving the same problem), its important to assess how the invention compares to yours and what the differences are. If your invention is for example smaller, or made of a different material, or some similar type of largely "cosmetic" modification, the patent office would likely reject your invention as obvious in view of that patent. However, if your invention works in a different way or approaches the problem from a different angle, it may be patentable.
If following your search you would like to meet with us to discuss the patentability of your invention and what you might be looking at as far as costs go, we would be happy to meet with you. We offer a free initial consultation and keep all such meetings strictly confidential.
You may also want to contact the Business Service Center (984-2272) to see what kind of information they can provide.