Not sure about flights mate, but if you want a well placed cool hostel then try 'Jazz on the Town' its not too expensive (about 22 quid per night), they have small dorms 4-6 beds and have really nice communal areas and bbq's on the top of the building on friday evenings. Alternatively, the YMCA on 53rd street has rooms with two beds, and you can use all the facillities (gym,swimming pool etc) for free, and its a 30 second walk from central park. Sorry i know you didnt ask about accomodation but hope thats some use for you.
JOE