If I understand your question correctly, which is "Is there someone who specializes in knowing if a home owner is about to be foreclosed upon?" If that is the correct interpretation, then it is difficult to specialize in "pre-foreclosure" since in order to know that information one has to know individual home owners who are delinquent on their loans.
I hope that helps. Let me know if you have any other questions.
Century 21 Advantage Gold
Brian M. Yoak