Hi biggnutts4life,
Welcome to the Mattress Forum! 
The first place I would start your research is the mattress shopping tutorial here which includes all the basic information, steps, and guidelines that can help you make the best possible choice … and perhaps more importantly know how and why to avoid the worst ones.
Two of the most important links in the tutorial that I would especially make sure you’ve read are post #2 here which has more about the different ways to choose a suitable mattress that is the best “match” for you in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) that can help you assess and minimize the risks of making a choice that doesn’t turn out as well as you hoped for that are involved in each of them and post #13 here which has more about the most important parts of the “value” of a mattress purchase which can help you make more meaningful quality/value comparisons between mattresses in terms of suitability, durability, and value.
When you reach step 3 of the tutorial and you are ready to start researching manufacturers and retailers to visit to test different types of mattresses then the better options or possibilities I’m aware of in and around the New York City area (subject to the quality/value guidelines I linked) are listed in post #2 here.
I’m looking forward to finding out what you end up deciding … and of course any comments or questions you may have along the way.
Phoenix