J. W. Pepper & Son sheet music retailer plus links to other musical resources
ChoralNet contains thousands of documents pertaining to the choral profession, and many more links to other sites
San Francisco Bay Area Chorus Directory a directory of choruses in Northern California that perform for the public and/or are open to members of the public
Bagaduce Music Lending Library
Alfred Music Publishers
Alle_noten a German site often has recordings or titles that aren't available in US)
Hal Leonard Publisher (doesn't sell sheet music, but you can identify it and often hear it)
Sheet Music Plus has an Annual Sale, a good time to bulk buy.
Hear the Choirs Sing contains Alphabetized snippets of LOTS of choral pieces.
Choir!Choir!Choir a selection of recordings of a Toronto based young community chorus singing lots of newish stuff.
The Choral Project auditioned touring chorale in San Jose
Santa Clara Chorale auditioned group performing a classical repertoire
World Harmony Chorus - choir repertoire from a wide variety of ethnic sources and folk traditions
The Valley Chorale auditioned performance oriented chorale concentrating on sacred, classical, and old standards
Schola Cantorum auditioned group performing a classical repertoire
Menlo Park Chorus community chorus for popular and classical arrangements often with orchestral accompaniment
Voices in Harmony barber shop quartet harmonies in large group setting
Peninsula Women's Chorus a Palo Alto chorus committed to excellence in performance of diverse and challenging choral literature for women's voices
Orchard City Community Chorus a group of singers from Campbell area whose common bond is the love of music and singing, and their desire to share their talents with each other and the larger community. (Auditioned for part placement only)
Sunnyvale Singers an unauditioned group of singers from the Sunnyvale area singing a wide variety of genres within the choral repertoire.