Canadians are fairly lucky in that we seem to have fewer geo-restrictions on what we can get via the Kindle store than people in other countries.
But still, there are titles and authors that we can't get at all, and recently a lot of the promotional freebies from publishers who used to include Canadians in on the deal are full price to us now. Also, certain widely-advertised promotional pricedrops simply don't appear for us, which can be frustrating if you see a novel you're interested in being promoted as "$2.99 for a limited time!" and it ends up being $9.99 when you go to buy it.
Sometimes this runs along publisher/imprint lines.
For example, none of Subterranean Press' e-book editions are available to Canada, which is a shame, because they're DRM-free and I like to support small specialty publishing houses when they put out stuff I like, especially when it's by an
author whose work I've previously enjoyed when I sampled it for free in the Hugo Awards voter packet.
Similarly, you can't get certain of Canadian science-fiction author Robert J. Sawyer's works or anything by also Canadian mystery writer Louise Penny.
They are both published by Tor and Minotaur imprints respectively, whose parent company Macmillan has a habit of doing that from time to time. Although not consistently since while Sawyer's
Calculating God and his latest works are not available, his entire early Quintaglio Ascension trilogy with the dinosaurs in it can be gotten for the same price in Canada as in the US.
Sometimes the disparity works to our advantage, as Agency 5 books that can't be discounted by Amazon in the States sometimes end up being discounted in Canada. Their price for
Rollback is 6.99, ours 5.59.
Probably the best thing to do is draw up a list of authors/titles you're interested in, set your country in the Manage Your Kindle page on the Amazon site, and start browsing in the Kindle store to see if you run into any issues regarding availability/pricing, especially if you notice a particular author/imprint you tend to follow having a pattern of unavailability.
Hope this helps, and welcome to MobileRead!