There is a CD publisher called Quentin publications, who is reproducing Asa Walker Slayton's SLAYTON HISTORY AND GENEALOGY. The book can still be found occasionally(see the posting by Michelle about an auction of the books plates on this site). This is not an endorsement of thier presentation but simply a way of letting you know that you can get access to the contents of this ca1899 book.
At one time, Mt Holyoke College in Mass loaned me the book on Interlibrary Loan. This book is in my opinion the best place to start, if you do not have it.