Well, 98% of the plants do not grow well up north or in Canada like I do. In the summer, MOST, do okay, the summers can be a bit harsh to some though.

Some plants, like S. purpurea ssp. purpurea grow up into Canada however, and D. rotundifolia, D. filiformis var. filiformis, and D. intermedia.

It's nice to see you are interested to see where you can get them!

You can get them at a few different places (I do not recommend eBay, 99% of the people selling them are idiots, I only know of one grower who grows them fairly well, but even then, there are better sources)

www.Flytraps.com - This place has TONS of plants in their pots and not in their pots (I recommend the 'in the pots' version, due to the fact that you don't have to do it, and they have the right soil, growing carnivorous plants in any soil with ANY type of nutrients or fertilizer = death. Their carnivorous habit evolved due to poor soil, it burns their roots and kills them. Their roots are undeveloped, only used to anchor the plant and to drink water. Most plants, such as Dionaea, some Drosera, a few Pinguicula, and all Sarracenia (but a bit less) do not have a high risk of overwatering, as they live in bogs.
www.CaliforniaCarnivores.com
A guy who wrote a book, Peter D'Amato made this site. He has a few rarieties.

For information, you can go to www.Sarracenia.com and go to the FAQ, if you plan on growing Venus Flytraps, there is a specific section, however, General Q's and the Taxonomy give a very good beginners indepth on it. The author is also humorous, and personally answers emails, he's never not answered one of mine! His name is Barry Rice, and he too has wrote a book about the plants.