TPYD - I noticed your location and I am fairly local. Is the 40th(or 40th's) you have been looking at the ones at German Star Motors? If so you may have some additional saving opportunity if you don't care about some options first I will answer your questions in order though........
1 - A Canadian 40th new was $48,498, A american 40th new was $38,860
A 2013 base+sport new in canada $46,800
2 - Search the forum the steering lock is not to be feared and easily fixed there is 3 options
3 - All 370Z are made in Japan and sent to either country, both countries have different requirements for the build. In short Canadian models have more standard - like a fog light is stock where as in USA it is an option, in Canada we also require a spare tire where as in the states some do not require you to have one.......I am sure theres more I could go on if you want.
4 - As Firehawk said you will get hit the hardest with the depreciation if you buy the 2013 as it hasn't been hit very hard yet, where the 2010 has already depreciated the fastest it ever will in the life of the car so you will regain from resale more on the 2010 IMO(not just 40th owner biased
)
5 - Again as Firehawk said end of the month is normally the best time to get a deal on a car
6 - I think the sticker price is to cheap but I could be wrong, online a base alone is $40,978 add sport @ $4000 and it is adding up plus taxes and other fees your getting up there quick. If your budget is $30-32K you will need to look used.
Now back to the talk about the American 40th's in the GTA. If you go in with all the facts and know what you are talking about I am sure you can get a much better deal
I think German Star Motors is just hoping to sell the cars to people who are uninformed on the differences and make a larger mark up because they brought up a bunch of used 40ths from the states .......IMO if your in Canada try and wait to find a used Canadian 40th they come fully load sport/touring/nav and you can get your choice of MT or AT if you really wanted an AT 40th where as the American 40th has no nav and only comes MT