For further reading and study: The standard text of Dickinson's poems is Thomas H. Johnson's three-volume The Poems of Emily Dickinson (1955), the first text to bring together all of her poems in a form reasonably close to the way she wrote them. Johnson includes early versions and variant readings of the poems. Johnson also edited a one-volume edition, The Complete Poems of Emily Dickinson (1960), in which he selects the "final" single version of each of her 1775 poems. For a complete discussion of the incredible history of the editing and publishing of Dickinson's work, from the first edition in 1890 clear up to Johnson's edition in 1955, see R.W. Franklin's The Editing of Emily Dickinson (1967). One of Franklin's major concerns is how we can reconstruct the "fascicles," those little hand-sewn books of manuscript poems that Dickinson so carefully constructed. Franklin's concern with this problem led to his editing The Manuscript Books of Emily Dickinson (1981), a two-volume collection of photoplates of all the manuscripts of her poems that made up the fascicles, given in the order of the various fascicle-books as Franklin has reconstructed them. Franklin has now edited his own complete three-volume edition of Dickinson's poetry that supersedes Johnson's edition, though it still has problems: The Poems of Emily Dickinson (1998). Ruth Miller's The Poetry of Emily Dickinson (1968) also discusses the history of editing Dickinson, and argues for the importance of reading the poems as fascicles; Miller finds a coherence of theme in the various fascicles. Recent books that build on the necessity of reading Dickinson's poems in the fascicle-context are Sharon Cameron's Choosing Not Choosing: Dickinson's Fascicles (1992) and Dorothy Huff Oberhaus's Emily Dickinson's Fascicles (1995).
A companion volume to the Johnson edition of the poems is the three-volume edition of The Letters of Emily Dickinson (1958), edited by Thomas Johnson and Theodora Ward; the letters are as elliptical and often as wonderful as the poems. A one-volume Selected Letters, also edited by Johnson, appeared in 1971.
Richard Sewall has written a vast biography, The Life of Emily Dickinson (1974), two volumes organized around the various family members and friends who were close to Dickinson. Jay Leyda has compiled a vast miscellany of things that Dickinson said and wrote and heard and read, month by month; it's called The Years and Hours of Emily Dickinson (2 vols., 1960). Thomas Johnson offers a more concise narrative of the life and a good overview of the poems in Emily Dickinson: An Interpretive Biography (1955). Cynthia Griffin Wolff's Emily Dickinson (1988) is a big biography that shapes the life and poetry into a satisfying whole. The most recent full biography, Alfred Habegger's My Wars Are Laid Away in Books: The Life of Emily Dickinson (2001) is reliable and offers a straightforward narrative of the details of Dickinson's life.
There is a lot of criticism on Dickinson; much of it is not very useful; a good deal of it likes to play the "secret love" game, looking everywhere in Dickinson's work for signs of sad love affairs, trying to identify every "He" as an actual person. Some books worth looking at: Charles Anderson, Emily Dickinson's Poetry: Stairway of Surprise (1960), which clusters her poems into thematic boxes like Ecstasy, Despair, Wit, Words, Center, etc.; John Cody's After Great Pain: The Inner Life of Emily Dickinson (1971), a big psychoanalytical study that is challenged by and updated by Vivian Pollak's Dickinson: The Anxiety of Gender (1984); Albert Gelpi, Emily Dickinson: The Mind of the Poet (1965), placing her in the context of 19th-century New England and the Romantic movement; Brita Lindberg-Seyerstad, The Voice of the Poet: Aspects of Style in the Poetry of Emily Dickinson (1968), with intensive discussions of Dickinson's diction, prosody, rhetorical patterns, syntax; Robert Weisbuch, Emily Dickinson's Poetry (1975), wich views her poems as one vast unified work, and focuses on the unique ways she structures her poetry: analogical collections, anti-allegories, etc. Edith Wylder's The Last Face (1971) is the strange book that sees the dashes as elocution markings. Shira Wolosky's Emily Dickinson: AVoice of War (1984) challenges the idea of Dickinson as a solitary and isolated poet, viewing her in the cultural context of the Civil War. Some recent illuminating feminist readings of Dickinson include Vivian Pollak's Emily Dickinson: The Anxiety of Gender (1986), Paula Bennett's Emily Dickinson: Woman Poet (1990), and Mary Loeffelholz's Dickinson and the Boundaries of Feminist Theory (1991). I also like Martha Nell Smith's Rowing in Eden: Rereading Emily Dickinson (1992), which contains many illuminating readings of the poems and begins the now-raging controversy about how Dickinson's manuscripts should be transcribed (or whether her poems should only be read in the manuscript forms in which she left them).
The bibliographic tools for Dickinson's work have become quite sophisticated; one of the most amazing is Joseph Duchac's The Poems of Emily Dickinson: An Annotated Guide to Commentary Published in English, 1890-1977 (1979), over 600 pages that lead you, poem by poem, to virtually everything, up to 1979, that has been written about any particular poem.
A good collection of criticism is The Recognition of Emily Dickinson, edited by Cesar R. Blake and Carlton F. Wells (1968), which offers a good selection of views from 1890 to the 1960s and allows you to see the development of her reputation. A more recent collection that illustrates the current debates in Dickinson criticism is A Historical Guide to Emily Dickinson, edited by Vivian Pollak (2004), and The Emily Dickinson Handbook (1998), edited by Gudrun Grabher, Roland Hagenbuechle, and Cristanne Miller, gathers illuminating essays covering the whole range of approaches to Dickinson.