Hi, I have been living in Mastic Beach, NY, for almost three years. I chose this location because I could find a home, near the water, with views that I find breathtaking, at a very affordable price. There are many homes for sale here: all are close to the Great South Bay, a few minutes drive over a bridge to Smith Point and the ocean beach. You can take the train from Mastic-Shirley station to Manhattan every morning (you do NOT have to drive to Ronkonkoma, unless your schedule doesn't fit LIRR's--there are more trains from Patchogue, too).
There is a community effort underway to incorporate Mastic Beach as a Village. The boundaries have been proposed, a petition done and submitted. The next stage is for a public meeting to validate the petition (February 22nd 2010), and then, if/when validated, the next stage will be a vote on the decision to Incorporate.
This is an exciting time in Mastic Beach! See the link below to see what a beautiful place this is--and do contact me if I can help in any way.