Give me a call at (516)410-3594 or shoot me an email at Arlynn@ArlynnPalmer.com and I will be happy to find that information for you.
In the meantime please visit my website at http://www.ArlynnPalmer.com where you can find FREE Buyer and Seller Reports, FREE School and Neighborhood Reports, a Monthly Newsletter and other valuable real estate information.
The links from the previous responses are correct but I can do it for you in just a few minutes if you'd like. I just need the address. Call me if you'd like a quick answer.
Lic Assoc. Broker
Prudential Douglas Elliman Real Estate
Have you checked your general tax bill. You will find it their. Otherwise you can go to the Nassau County website and look for the property search tab or index. Once there you can put in your address and get a variety of information about your property including your section, block and lot numbers. They are at the top of the page.