Poets.org (from the Academy of American Poets) http://www.poets.org
Poets http://www.english.uiuc.edu/maps/poets.htm
Famous Poets and Poems http://famouspoetsandpoems.com/
Giggle Poetry http://www.gigglepoetry.com/index.aspx
Poetry Tool (for finding poets and poems) http://poetryfoundation.org/archive/tool.poet.html