We want to fly from Manchester, U.K. Mid to late December, stay in New York city for 4 days for some Xmas shopping.

Chosen Answer:

www.statravel.co.uk are whipping the cost of airfares compared to other agents. However, you have got to be a student or buy a special card which still makes it cheap. Check it out! I’ve travelled all over the world and they got shops in all major cities internationally so you can actually deal with them face to face if there’s a problem.
I also recommend the Thirty Thirty Hotel in NYC – located near everything, decent accomodation and good price. You will love it