Not to argue with the sentiment, but to take it to its frivolous conclusion: According to Wikipedia[0], the letter A begins words approximately 11% of the time

Not to argue with the sentiment, but to take it to its frivolous conclusion: According to Wikipedia[0], the letter A begins words approximately 11% of the time. This only includes english, and is a distribution over all text, not book titles. It is, however, a decent proxy[1]. After that, I also assume regular English letter frequency for the rest of the letters [2]. Using these factors, there would be 14,175,136 books under the letter A. Aa has 1,157,683 books. That's over 3,171 years just to get to Ab. [0] http://en.wikipedia.org/wiki/Letter_frequency#Relative_frequencies_of_the_first_letters_of_a_word_in_the_English_language http://en.wikipedia.org/wiki/Letter_frequency#Relative_frequ... [1] A much better proxy would be to find the relative frequencies of book titles on Project Gutenberg. [2] http://en.wikipedia.org/wiki/Letter_frequency#Relative_frequencies_of_letters_in_the_English_language http://en.wikipedia.org/wiki/Letter_frequency#Relative_frequ...