Some of the helpful tools of the trade:
Google -far and above the most helpful for free searching. http://www.google.com/
to restrict the millions of returns on searches, put keywords in quotes.
For example, John H. Miller Peru, IN will bring a lot of useless returns to do with the country Peru. Putting the search as "John H. Miller" "Peru, IN" and various combinations like that will help. Use the minus sign to exclude, (-missouri or something), use the plus sign to force the results to include (+John or something).
Ancestry -the most helpful, but will cost you http://www.ancestry.com/
County Histories and other items using GoogleBooks http://books.google.com/bkshp?hl=en&tab=wp
Library edition of Ancestry and Census records (often your public library will allow access to a limited part of Ancestry.com databases at the library itself.)
The now and then postings of the discoveries and contributions of the Miller and Bechtold families .