The Academy of American Poets has a brief biography, followed by an extensive list of links.
Christian Science Monitor has a brief excerpt from an interview Oliver did with Steven Ratiner. The entire interview can be read in Ratiner's book, Giving Their Word -- Conversations with Contemporary Poets.
Earthlight Magazine has a brief critical essay on Oliver's poetry as nature poetry.
Modern American Poetry has critical essays on Oliver's poetry, along with a link to her poems online.
Montgomery College has a web page for Oliver that provides a short biography.