Online, consider releasing some content related to your book. Table of Contents, Preface, and Contributors are all great ideas that can be shared, in their entirety, that may encourage sales. For genealogy, another idea is the entire index. Giving the index away is arguably a good strategy, and for those who feel this is to much, offer a surname only (no page citation, given names, or other data) – as this lets potential buyers get an idea of what is in your book.
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