Where can I find Nissim Ezekiel's poem "Enterprise"?
You can read excerpts from the poem and analysis of it in the book Studies in Indian Poetry in English, edited by U.S. Rukhaiyar and Amar Nath Prasad. The chapter in which this poem is analyzed are online at books.google.com. Another book in which the poem appears, and that is also available at books.google.com, is The Poetry of Nissim Ezekiel; however, as in the previous book, the poem is excerpted rather than printed in full.
Because the poem is still protected by copyright laws, it is unlikely that you are going to find the complete text anywhere online. Your best option is to purchase a copy of Nissim's book Collected Poems.