For more info on obtaining data for NYC visit the:

You can build or approximate your own neighborhoods with the geographies listed below.

• PUMAs: statistical areas that have approx 100k people (ACS only)
• Census Tracts: statistical areas that have btw 1500 and 8000 people (2010 Census and ACS)
• ZIP Codes: used for mail delivery, population varies significantly (2010 Census and ACS)
• Neighborhood Tabulation Areas: aggregations of census tracts created by the NYC Dept of Planning

If you are looking for census data for NYC neighborhoods, consult the sources below. These organizations have taken small census geographies (like census tracts) and have aggregated them to create neighborhood data or have used other areas (like PUMAs) to approximate neighborhoods.