I've been to York before.

Don't look like a tourist.
Don't bring hefty sums of money around with you, be careful with your card and wallet.
I'm that paranoid person who keeps pockets of money around in different places, remembering where they all are in my head.
Be careful about bumping into people, and staring. Don't stare.

There are certain times of night when it's not good to stay out on certain streets.
I don't really remember what they were, but it's advisable not to stay out too very late.
Though it is really bright at night in the city, I watched a play and when I left the theatre I couldn't tell what time it was because the city lights made it seem kinda bright out, but if you looked further off the citys horizon the sky was completely black.

Do not take pedi-cabs or taxis. Take your time to learn about their subways, use the metro system.
The Empire State Building was okay. If you really like views and high places or if you're some sort of photographer.
It takes a heck of a long time to get up there, you will have to switch elevators to be able to go up to the top, and your ears will pop to adjust altitudes. But the view was pretty cool.

Cheesecake is good.
I don't know what i'd do if I were you, since you're not interested in shopping.
That's what it's known for, shopping. I mean, guh, go to diamond street and you'll know you're there because at the entrance there are diamond shaped street lamp things.

I liked watching plays and music things. Theatrics.
Saw Mary Poppins while I was over there, for old times sake.
She flew. Out from the stage and above the balcony seats, don't know exactly where to..
But it was interesting. Supercalifragilistic.

Hot dog stands, you see them around, everyone knows about them. Don't eat those hotdogs. Don't. Not good. Bad idea. Go find somewhere legit to eat.
Time's Square is kinda expensive but eh. Two blocks west there's some lines of places that were good eating.
I kinda wish I went to Hell's Kitchen. If you try eating there tell me how it turns out.