So you've decided you want to take some pictures of wildlife (or anything) and you want to know where to get some equipment to make those images the best they can be. For the brick and mortar crowd you can try:
Downtown Camera--Located right downtown (duh!) these guys have some of the best prices and they're very friendly and helpful, a big factor in my book. And they carry cool stuff like rangefinders. Their prices on used equipment are also usually excellent.
Vistek--Toronto's 'pro' camera store, Vistek has great selection and sometimes very competitive prices. Their salespeople however are a different story. Many of them seem to have drunk from the same vat of specially tart vinegar each morning and they really just aren't nice. The exception is on the upper 'pro' floor: I've often received excellent attention here even when I was buying something worth only about twenty bucks. So if you go to Vistek just be wary of who you deal with. If you do get a jerk just ask for someone else! That should show them. Used selection at is very limited.
Henrys--Toronto's traditional camera store, Henrys has expanded a lot in the last few years and seems to be moving more into the consumer electronics Future Shop-type market. What's more, their salespeople aren't very friendly either (there are exceptions) and to top it off they don't know much. But a deal's a deal, if they have one sure, and sometimes you can find a great deal on their eBay site. Otherwise I'd steer clear of Henrys.
DVshop--Located a little more to the west of the city, DVshop specializes mostly in video, but they have still camera stuff too. Their selection is limited but they often have truly great prices and a lot of stuff they don't carry they can order. Also, perhaps because it's not a big store they're extremely friendly and helpful.
And on-line:
Camera Canada--is not in Toronto at all, it's in London (yes, Ontario), but if you're in Toronto you can use them, can't you? They have a wide selection and the shipping is usually pretty reasonable. Compare prices before you buy. No used department but they do have a new 'trading post' where you can post or read ads that others have posted. I've never used this so I'm not sure how it works but it might be something you'd like to try out.
Kijiji--If you're not familiar with Kijiji, no, it's not a typo. This is a classified ad site where you can find all sorts of camera equipment available. Sure it's used, but camera equipment doesn't have nearly as much potential for hidden problems as does something like a car. If you run a camera through its paces when you go to purchase and it works then, well, it works. It's ever easier to check a lens, you just need to make sure there's no fungus or dust inside (or at least not too much dust) and no oil on the blades. Just as it says on the site however, only buy from local people that you can see and meet. Do not buy from a guy with a great deal who lives in Labrador or Kuala Lumpur.
B&H Photo--The largest camera store in New York (and heck, maybe the world) B&H Photo does a rip-roaring internet business. They're very honest and reliable and fast, but there is a good news/bad news aspect to it. The good news is THERE IS NO DUTY OR TARIFF ON CAMERA EQUIPMENT FROM THE UNITED STATES. You will have to pay PST and GST (and the exchange of course) but that's it. The bad news: if you buy a new camera or lens in the US in most instances the warranty is not valid in Canada. This is definitely true for Nikon, so always check with the respective manufacturer. What all of this means in effect is that you should avoid buying new cameras from the States, but a lens is probably worth taking the risk. For used equipment B&H have their own three month warranty. If it's any sort of camera equipment you can be almost sure to find it here, both new and used.
Adorama--another giant camera store in New York, and pretty much everything I said for B&H goes for Adorama too, though I find Adorama isn't quite as fast on the shipping front. Realize that even with the exchange you can get a lot of stuff cheaper at either of these places than you can in Canada.
KEH--Yes, also in the US, Atlanta based KEH is a HUGE online depository of camera equipment. They're also very reputable and offer a three month guarantee. They're very conservative about how they grade equipment so you'll probably be surprised at what good condition the equipment is in. KEH does charge a little more for shipping than B&H or Adorama, so like with everything, do your comparison shopping.
And that's about it for now, though of course there's eBay, but I don't recommend that, since there's just no way to know what you're getting.
And remember: the great thing about getting expensive camera equipment is you can usually sell it for close to what you bought it for, so buy, buy, buy!