Okay, this may seem like a dopey question, but how do I get to the NY tour?  Sometimes it seems to come up on the welcome screen, but usually it doesn't.  So if I want to select it, is that possible?  Or do I just have to hope for the best?

I was wondering the same thing about the Japan tour. It doesn't look like it's possible to get to previous tours unless you are lucky enough for it to show up on the welcome screen, and the older the tour is the less likely it will show up.

The tours usually go away at the next update.  I think the USA tour is gone now?

If you search around on the official MSFS forums, some people have posted the .pln files that went with the tours.

https://forums.flightsimulator.com/t/japan-tour-flight-plan-for-those-who-missed-it/309849

https://forums.flightsimulator.com/t/re-fly-east-coast-usa-tour-after-latest-update/340595