Poetry Foundation's brief but fascinating bio of the elusive lady poet. You can also find useful links to Dickinson's poems online, as well as some articles on other poems, if you're interested.
Similar to the Poetry Foundation site, here's another concise general information page on Dickinson's life and work.
A thoughtful blog entry from poet Jessica Smith.
The Dickinson Electronic Archives is an online center dedicated to Dickinson's work. It features rare images of writing by Dickinson, her family and friends, as well as transcriptions of the faint, hard-to-read 19th century script. Unfortunately, you have to have a password to access some materials, but you can still find enough on here to sate your curiosity (or your research requirements).
The museum's website includes a solid biography, some videos, and other resources.
Watch the real Hogwarts Express leave the station. It really does make crazy hooting sounds.
Watch a steam train zip by, and listen to it whistle.
One group sets out to prove that you can sing any Emily Dickinson poem to "The Yellow Rose of Texas," no matter how grim the poem is (in this case, the poem is "I felt a Funeral in my Brain")
This "preview" allows you to hear an almost-complete professional reading the poem.
The image of the railway train that pops into many of our heads is the Hogwarts Express!
Here's the only known photograph of Emily Dickinson.
Here's another famous poem about the arrival of the train, from Dickinson's contemporary, Walt Whitman.
The Complete Poems of Emily Dickinson, edited by Thomas H. Johnson.
Check out The Manuscript Books of Emily Dickinson, an awesome edition that includes facsimiles of all of Dickinson's handwritten pages.
Check out the Google Books preview for Dickinson scholar Domnhall Mitchell's book, which features a whole chapter about this poem.
Superstar poetry scholar Helen Vendler offers an elegant and brief commentary on the poem in her book, Dickinson: Selected Poems and Commentaries.