The Index Translationum from UNESCO contains two million records of books translated from over one hundred countries and spanning the years 1979 to 2009.(More recent years are in the process of being integrated into the system.) The information in this system is contributed by the national libraries of the cooperating countries.If you want to track a book’s history in other languages, this is a great place to start. For example, searching for Patrick O’Brian’s Treason’s Harbour from this page shows that this work has been translated into Spanish, French, German, Italian, Dutch, and Japanese. In addition, you can find numerous statistics, among them Top Fifty Authors (the fiftieth author being the mysterious “et al”, Top Original Language, etc. “Last updates” indicates the timeframe for materials that are being processed for inclusion. And partners provides a valuable list of national libraries’ and international organizations’ websites.