So I bought Philomena by Martin Sixsmith and it only cost me 99p. Happy days.
The book is based on the true story of an Irish lady called Philomena Lee, who searches for the son she had out of wedlock. The book also goes under the title of The Lost Child of Philomena Lee and focuses more, as the title suggests, on the life Michael/Anthony had after his adoption.
The book has also been made into a film starring Dame Judi Dench and Steve Coogan. I plan to watch the film in due course once I have read the book.
Philomena is a 2013 British-French-American comedy-drama film directed by Stephen Frears. It was screened in the main competition section at the 70th Venice International Film Festival where Steve Coogan and Jeff Pope won the award for Best Screenplay. At the 2013 Toronto International Film Festival it was awarded the People's Choice Award Runner-Up
The film is based on the book The Lost Child of Philomena Lee by Martin Sixsmith, which tells the true story of Philomena Lee's 50-year-long search for her son.