State campgrounds in New York are split into two groups: The Adirondack and Catskill Parks campgrounds are operated by the Department of Environmental Conservation (DEC) while state campgrounds throughout the rest of the state are operated by NYS Office of Parks, Recreation and Historic Preservation (OPR&HP.)
Most the DEC campgrounds are "no hookups" but there is water available every few sites in all the loops. A few like those adjacent to the St Lawrence River have full hookups.
OPR&HP campgrounds generally have many sites with water and electric hookups. The electric may only be 15 or 20 amp in some campgrounds.
All NYS camp sites are reservable through reserveamerica.com. Additionally, there is a website called New York State Campsite Photo Guide. The webmaster has photo-documented 49 state campgrounds (so far) across the state. There are several photos of each site, data on the site, and more. It is an amazing project which started with just one campground several years ago. Folks asked him to do other campgrounds and it just exploded from there.
http://www.campadk.com/campsitephotos.php
There's also a Facebook page that's part of the same project:
https://www.facebook.com/groups/nystatecampsitephotos