If you are going to New York for four days, being November, it will be cold.
Therefore, Boston and Washington, two places that aren't too far away will also be quite cold. Also, they are also big cities and after doing New York, ye might be in the need for a change. New England would be a great place to visit in the October as people come from all over the states to see the Trees! Supposed to be fantastic... sister was there and can vouch for that. However, by November it also will be quite cold.
Yeah, think Grand Canyon, San Fran, San Diego, Vegas, Hawaii would be all options. Apart from San Fran, all should be a lot warmer that time of year. The carribean and florida would be other options as you can fly there direct from New York.
However, if you are flying internally in the US, it would be worth your time checking out
www.jetblue.com
This is the US low cost carrier. Flying internally can be expensive in the States.
Also, check out
[broken link removed]
Navigate to the right hook and then the tuesday travel page.
You can ask for back issues to some of the places you could go to.
Also, should text in and ask the guy that does the show. He is with the lonely planet and really knows the states well.