Schubertline: instant online printing of classical songs, which may also be viewed and heard in any key. Established in 2001, this is now the web's largest transposable library of opera arias, German lieder, French mélodies, English songs etc. by hundreds of composers.

http://www.classicalsinger.com/

http://www.vocalimages.com

http://www.operastuff.com/voice.html

http://www.ncvs.org/ncvs/about/people/gould.htm

http://www.ncvs.org/ncvs/info/singers

http://www.worldzone.net/music/singingvoice

http://www.joyinsinging.org/

http://www.choralnet.com

http://www.voicefoundation.org

http://www.searchmusicnetwork.com