[brian_spiering]

The Real Book is an excellent resource for what it is. However since it is the primary book of jazz, it can have too much of an influence. The Real Book has a limited number of songs and entire subgenres of jazz are not represented. The structure of the songs is relatively narrow. Songs are rarely added.

[neonscribe]

There are now six volumes of Real Books from Hal Leonard, plus a several others organized around genres or artists, plus the Sher Music books. A few thousand songs. Not every player has every book, but they are all available. Most songs are available for purchase for a few dollars each as downloadable PDFs.