also try the town records to see who has lived on the street for sometime and send the letter directly
to them. If there is a neighborhood association find out who is the head of it, and contact them. They
just may have heard of someone interested in selling. All it takes is one good contact - good luck! If
I can be of further assistance please reach out to me - Nancy Butterly, Realtor, email@example.com
So yes, used properly it can be an excellent tool in your search if you know exactly what you want.
One key is to make sure your letter doesn't look like a mass mailing letter. Handwritten is good. Tell the owner why you're interested in buying on their street or their neighborhood. If you can find out if the homeowner is upside down on their mortgage, tell them you're prepared to work with whoever holds their mortgage and do a short sale (if that is true). You can get some great deals buying a short sale. Have someone help you who's done it before.
I think it's a great idea. Even better, hire a Realtor to do the work for you. He/she will have the name/s of the owner, send it on letter head which will take away the "stalkerish" feel and more serious.
Hope this helps!
Make sure you know the values for the neighborhood, so if you do get a response you be able to move forward.