Umm, in US currency, it's usually somewhere around $11 each. I dunno about canada, though.
I just got one a few days ago, and here's what I know so far.
(Usually) every hour, there's something different and special going on! You can check it on "Today's Activities" if you open up "Things to Do". Usually sales, but sometimes you can get free things, like some free KinzCoins or a coupon. There's something called the Curio Shop, and the shopowner, Arte, sometimes has some rare items that you can NOT get anywhere else. Also, you can go gem-hunting there, and if you collect every single gem, you can get the one and only Crown of Wonder that almost everybody wants. Also, there are things on sale in the "W-Shop" everyday. When you take care of your webkinz, try to make your happy, health, and hunger meters as high as you can. It could get sick, so be sure to take good care of it. If it does get sick, visit the Clinic, and the doctor (Dr. Quack) will prescribe some medicine. Then, after you buy it, your webkinz will be fine. Be sure to excersise it every day. You could buy treadmills, pools, trampolines, etc. to excersise it. You can decorate your house any way you want to! A small room is 500 kinzcoins, medium is 700 kinzcoins, and a large room or a yard are 1000 kinzcoins. Webkinz is kinda like caring for a real animal, except you don't have to actually do the stuff. Also, you can talk to the pet, dress it up, play with it, etc.. If you have any friends on your friend-list, you can challenge them to a game in the tournament arena, chat with them by using kinzchat, and go to their webkinz house. Kinzchat is safe--you don't get to type what you want to say, but there is a list of words/phrases that you can choose from to interact with them. Also, webkinz is educational! There's something called "Quizzy's". It asks you questions, and to me it's the best way to earn money. Each correct question earns you 5 kinzcoins. Each quiz has 50 questions, so if you get all of them right in one quiz, you get 300 kinzcoins, and it only takes about 15 minutes (at least to me it does)! I'd give it a rating of 9/10. (i didn't give it a full score because SOMETIMES there are a few glitches...but otherwise, it's great.) Uhh, I didn't include everything in this paragraph because there's too much.
*breathes in and out* Actually, you could just see the tour on the bottom of the webkinz-main page. It has about everything you need.