Been playing on my iPad in California since yesterday...
1.Go to Settings
2.Select iTunes & App Store
3.Select your Apple ID name
4.Select View Apple ID
5.Select Country/Region
6.Select British Columbia, Canada for example
7.Delete your payment method
8.Replace your zip code with a BC, Canada one (V5Y 1V4)
9.Accept terms and conditions blah blah
10.Go to App Store and search Blizzard entertainment inc
11.Download Hearthstone
You can follow these steps again back to your normal settings once its installed. You can also add a payment method and purchase decks.
Edit: Available in NA now, without any trickey! https://itunes.apple.com/app/hearths...625257520?mt=8