Music
http://www.wwnorton.com/college/music/concise-history-western-music4/
http://glencoe.mcgraw-hill.com/sites/0078297567/
http://www.wwnorton.com/college/music/rockhistory2/
http://www.routledge.com/music/
http://www.wwnorton.com/college/music/grout8/
http://www.glencoe.com/sites/colorado/student/music/assets/gln_music_podcast_student.html
http://www.wwnorton.com/college/music/jazz/
http://www.wwnorton.com/college/music/enj10/essentials/
http://www.wwnorton.com/college/music/enj10/complete/
http://www.wwnorton.com/college/music/enj10/short/
http://glencoe.mcgraw-hill.com/sites/0002022011/
http://www.routledge.com/textbooks/9780415992091/weblinks.asp
http://cw.routledge.com/textbooks/9780415961011/resources.asp
http://www.routledge.com/textbooks/9780415997256/audio-examples.asp
http://glencoe.mcgraw-hill.com/sites/0002032011/
http://www.routledge.com/textbooks/MusicEducationinYourHands/student-resources.asp
http://glencoe.mcgraw-hill.com/sites/0002012011/
http://www.glencoe.com/sec/music/student/index.php/ch
http://www.routledge.com/textbooks/worldmusic/2ndEd/listening.asp --includes audio clips
http://www.glencoe.com/sec/music/ecm/index.php/al
http://www.glencoe.com/sec/music/student/index.php/mu
http://highered.mcgraw-hill.com/sites/0072415665/student_view0/index.html
http://mailer.fsu.edu/~mbakan/index.html
http://www.routledge.com/textbooks/9780415960656/resources.asp
http://www.routledge.com/textbooks/9780415991476/questions.asp?unit=1
http://www.routledge.com/textbooks/9780415960717/
http://www.mhhe.com/socscience/music/index.htm
http://highered.mcgraw-hill.com/sites/0073526576/student_view0/
http://highered.mcgraw-hill.com/sites/007249865x/student_view0/index.html
http://highered.mcgraw-hill.com/sites/0073401358/student_view0/index.html
http://highered.mcgraw-hill.com/sites/0072852607/student_view0/index.html
http://highered.mcgraw-hill.com/sites/007313774x/student_view0/index.html
http://www.mhhe.com/socscience/music/benward/train.htm
http://www.mhhe.com/socscience/music/benward7/site/
http://auth.mhhe.com/socscience/art/benward_white/student.mhtml
http://auth.mhhe.com/socscience/art/benward_white/instructor.mhtml -- a complete student workbook for music theory is available here if you scroll down a little; likewise, while it says you need a password to access the teacher's manual, you don't. SO this amounts to a complete course in music theory for free.
http://highered.mcgraw-hill.com/sites/0697340635/student_view0/index.html
http://highered.mcgraw-hill.com/sites/0073401390/student_view0/index.html --click on "sitemap" for easy access to the resources here (including student projects, activities, audio examples, flash cards, and webquests!). I really like these resources!
http://highered.mcgraw-hill.com/sites/0073401420/student_view0/index.html --includes listening guides
http://highered.mcgraw-hill.com/sites/dl/free/0073401420/773185/Music19thCenturyAmer.pdf
http://highered.mcgraw-hill.com/sites/0073401412/student_view0/index.html
http://highered.mcgraw-hill.com/sites/0073526568/sitemap.html
http://highered.mcgraw-hill.com/sites/007340134x/student_view0/index.html
http://www.mhhe.com/socscience/music/white-miow/student_index.mhtml
http://highered.mcgraw-hill.com/sites/0072451793/student_view0/index.html
http://highered.mcgraw-hill.com/sites/0073401374/student_view0/index.html --with demos of different styles
http://highered.mcgraw-hill.com/sites/0072977590/student_view0/index.html --singing with some scores and audio recordings of accompaniments!
http://highered.mcgraw-hill.com/sites/0073401404/student_view0/index.html
http://highered.mcgraw-hill.com/sites/0073526576/student_view0/
http://highered.mcgraw-hill.com/sites/007298919x/student_view0/index.html