Ok, the original idea was buy the Ender’s Game book (by Orson Scott Card), but I dont find it :( so, I bring to home the Ender’s Shadow and Shadow of the Hegemon books (parallel novels to the Ender’s saga).
I just finished the Ender’s Shadow a few hours and… wow! what a book! not a masterpiece but works. Heres a link to the original short story. By the way, check the kick ass covers by Leo Flores, unfortunately, I don’t find links to any gallery of his work.