Near the end of the episode, Mac, Stella, & Flack respond to a doctor's residence which is supposed to be near Park Ave and 40th street. When Flack summons an ambulance, he gives the address as "1430 West 40th." If the location is near Park Ave, it would be on East 40th Street as Park Ave is east of 5th Ave, which is the demarcation of the transition from East to West in Manhattan.
In addition, 1430 West 40th Street would be in the middle of the Hudson River given the street numbering scheme in Manhattan.
The so-called 'Amityville Horror House' is located outside of the NYC limits in Suffolk County, on Long Island. Suffolk County has their own county-wide police force that provides the same law enforcement services that the NYPD does, including forensics. The county sheriff's responsibilities are limited to running the county corrections system (jails) and providing security services at courthouses, including prisoner transfers. Thus, there is no sheriff of Amityville and no reason for CSIs to be called out from NYC (other than some LA-based writers trying to figure out a way to work the Amityville Horror house into an episode of CSI NY.)