There is a book out on Nobunaga's niece Ogou. She was the youngest of Oichi's three daughters. Ogou would later marry Tokugawa Hidetada. This will be a good read leading up for the 2011 Taiga drama.
Oichi's three daughters. Chacha would be Hideysohi's concubine, Ohastu married Kyogoku Takatsugu, and as mention above, Ogou married Tokugawa Hidetada.
The link to the book: http://astore.amazon.co.jp/sengokuwalker-22/detail/4140055707
Nobunaga no tame!