If you are gonna make a one race trip, I would try to plan to hit the Petit LeMans next year. Although at this point it hasnt been added to the WC schedule.

The race is a blast and is a full weekend event and party.
Another good one would be the DC race. Although not as long a race as Petit or as neat a track, it has a lot of stuff to do if you have never been to DC. So you could make a true vacation out of it.
You could also do that with Mosport as well, since you could do some traveling and hit places like Montreal and Niagra Falls before or after race weekend.
Anyway, just some ideas. I used to travel back east for at least one race a year and to see family. But once you have hit a few, it just want more.
You could also look into the SCCA. I know they have some tracks out your way and that would allow you to get involved and have some fun with some amateur road racing. I would have been able to live with that, but the closest place for that from Utah was Denver and it was just too far to go for amateur racing. But now that I have an amateur track within an hour of home I go to that about once a month to get a fix.
Anyway, I will envy you over the winter since there is no racing and, in the DC area, no snow or mountains.
Have fun for me.