New York City Department of Health and Mental Hygiene
Their Data and Statistics Surveys page lists all their products. Data access varies by product and can be via their EpiQuery interactive web site, direct download of pubic use files and/or printed reports
NYC Open Data
A repository providing access to over over 800 government-produced datasets. Most are data tables and some are spatial files.
Links to download for spatial files are in the "About" link for a datasest rather than the "Export" link.