Find out the name and address of the person or company that used your photo. This is necessary to proceed in court against that person or company. (Yes, there are mechanisms that could be used to force the disclosure of such information by a third party, but it would be expensive to do this.)
Seeing as your email request fell on deaf ears, if you can come up with the name and address of the person or business (let’s call this entity the “defendant”), then hire a Canadian lawyer who practices intellectual property in the city where the defendant resides. You will be asked by the lawyer to provide at least a few thousand up front as a deposit against your legal fees. Since this is a trivial matter being pursued on principle, you will probably have difficulty in finding a lawyer to take on the matter, for usually folks who call in on this sort of thing waste the lawyer’s time complaing about the principle of the matter, but are ultimately unwilling to come up with the cash to pay for the lawyer’s time. (Different lawyers have different policies with dealing with trivial matters. To dissuade people from wasting my time on this sort of thing, I usually tell them that I would be pleased to speak with them at a few hundred per hour paid in advance prior to booking the appointment, and that if I then take on the case I would require a retainer deposit of about fifteen K. It very quickly separates the shit from the Shinola.) Probably your best bet would be to find a firm with an articling student who is interested in intellectual property, for it could be a good learning experience for the student.
The lawyer will send a demand letter threatening a lawsuit if the photo is not taken down, and odds are that that will be the end of that, given that only a loon would keep the photo up and defend such a matter. You’d get the bulk of your retainer deposit back, and go on your way.
If the photo is not taken down, then the lawyer will commence a lawsuit against the defendant in the defendant’s city, asking the court to order the defendant to take down the photo, to pay damages to you, and to pay your legal bill. Assuming that you can prove that it was your photo, then the odds are that you will get an order requiring that it be taken down, that you will only get nominal damages (a few bucks if that), and that you will get part of your lawyer’s bill paid (usualy two-thirds or less unless the defendant is a real jerk). If the matter were a quick and simple win, if costs were ordered, and if your lawyer was actually able to collect the costs award for you (often winning a case is easy, but often collecting on the court’s order is not), you would still be out of pocket a few grand or more.
Since the matter is for equitable relief rather than easily quantifiable damages, the odds are (depending on the province) that it would be heard in a superior court rather than a small claims court, which unfortunately means that it would cost a bit more and take a bit longer than if it were a small claims matter. That being said, as far as lawsuits go, it would be a simple claim and motion to put together and a simple matter to fight should the defendant not then take down the photo.
I appreciate Exapno Mapcase’s post, but please note that assuming that you can prove that you created the photo and that you have not given up your rights to it, then you already have copyright for it in Canada, despite you’re not being in Canada, and despite it not having been created in Canada. In Canada you do not have to have anything on the photo identifying that it is under copyright.
Similarly, in Canada you do not have to register the copyright. DMark’s most excellent post is on target, but note that registering a copyright in Canada is not necessary to win a copyright lawsuit in Canada. You must prove that you hold copyright to the judge. There are to ways of doing this. One way is to get your evidence together and present it in court to the judge. The other ways is to get your evidence together, present it to the copyright registration folks at the Canadian Intellectual Property Office, receive a Certifiate of Registration, and then give that cetificate to the judge. If the infringement is a one-of thing, as appears to be with your one photo, then there is little benefit to going through the registration process. If, however, you expect repeated infringement from a number of parties, then it makes more sense to get the work registered and usually not have to prove everything from scratch for each and every lawsuit.
All but the trial could be done without you having to attend in Canada. Conferences with the court could be held over the telephone, and motions would be done via affidavits rather than on the stand in person. You would have to attend the trial as a witness to present your evidence, but the odds of this being defended to the point of going to trial are remote.
Various posters have given you their opions as to whether or not to go forward with a lawsuit, ranging from beowulff and CairoCarol recommending that you not proceed, to mhendo’s “Fuck that.” I suggest that you look at the matter as if your were running a business. What is the benefit of a lawsuit? The photo being taken down. What is the harm of not proceeding with the matter? Only the principle of the matter. What is the cost of the lawsuit? Likely a few grand or more. What would be the best use of a few grand or more in the development of your business – spending it on taking down a photo, or spending it on a new Nikon D4? Quite simply, only wealthy people and crazy people take trivial matters to court when the only benefit is the principle of the matter. Regular folks just write off trivial matters like this as a cost of doing business.