Keep running into dead ends

[Sergio L. Garza]

I've been finding vacant homes either through probate notices or driving through neighborhoods. Anyways, I'll check with the local appraisal district information and there's no phone number or name or other address to the owner. Plenty of neighbors from several vacant homes I have encountered tell me the person who lived there is deceased. There have been instances where I do find someone who is an heir and I'll send them a letter in the mail or I'll call them, but there are just so many dead ends, whether the heir is not communicating to there being no one available to communicate with. 

Are dead ends common when it comes to probate/vacant homes? Is there anything I can do before they foreclose? What do I do other than continuing my search for motivated sellers?