I'd advise checking out the new Silent Barn gigs over the Knitting Factory, they are now basically just a front for booze.
https://sites.google.com/site/paestheticsllc/home/shows
Iv'e had friends stay at the White House hostel in Manhattan on Bowery and were happy but not for 3 weeks. Good luck, NYC is expensive and a lot of the cheaper stock is being used by survivors of Hurricane Sandy. I know 2 people who literally lost their homes in this disaster.