There is no such thing as Naruto conventions however there are such things as anime conventions which will definitely have something to do with Naruto, so just do a bit of Googling and there should be a website for all the conventions in your country!
there arent any specific conventions for them but there is an anime convention. Mechacon in New Orleans, Louisiana
naruto is not on the air in Canada but you can watch it online for free
You can buy the DVDs at most anime conventions.
There are 43 conventions in Canada in 2011. Go to the 'related link' below and a search will show you dates and locations.
You can watch it online at these sites: Naruto: Animefreak.tv or Onepieceofbleach.com Naruto Shippuden: Animefreak.tv or Naruto.com
Naruto Ultimate Ninja 4: Shippudden.
Canada is part of the Hague Conference (making them a "member state") There are roughly 40 Hague Conventions (individual treaties) on a variety of topics. Canada has Ratified or Acceded (legally-nuanced way of saying they signed a treaty) to 4 separate Hague Conventions. This is the chart of every country and which hague conventions they have signed:
Sadly it dosn't look like it's coming any time soon :(
No
If you visit the Watchtower's official website there is a link at the bottom to another site giving details of 'publication downloads'. Once there, there is a 'look up' tab which will give you the facility to look up conventions in Canada. There are 43 conventions in Canada in 2011.
There is naruto pedia and naruto arena
No, there won't be any more Naruto after Naruto Shippuden.