here are some articles regarding building a jazz library focasing on vocals
1917-1950 - http://www.allaboutjazz.com/php/article.php?id=18804
1951-1968 - http://www.allaboutjazz.com/php/article.php?id=18803
1969-2001 - http://www.allaboutjazz.com/php/article.php?id=18726
1917-1950 - http://www.allaboutjazz.com/php/article.php?id=18804
1951-1968 - http://www.allaboutjazz.com/php/article.php?id=18803
1969-2001 - http://www.allaboutjazz.com/php/article.php?id=18726