Wow. Flavorwire has nailed it: a superbly-chosen list of fifty essential literary biographies. Click through the list, read the captions, and you are sure to find a book that celebrates an author whose work you enjoy.
I can vouch for the excellence of Hermoine Lee on Virginia Woolf; of Justin Kaplan on Whitman (on Twain, too, though that book is not on the list); of Buell on Emerson, though I have not read the book (Buell’s works New England Literary Culture and Literary Transcendentalism are definitive in their fields); and of Ellmann on Joyce.
I am surprised that Walter Jackson Bate’s monumental biography of Samuel Johnson is not on the list. It’s one of the great books of the twentieth century. Add it. Greenblatt’s Will in the World is very fine from its chosen perspective, but there are two other, more traditional books about Shakespeare worth reading: William Shakespeare: A Compact Documentary Life, by Samuel Schoenbaum, and Schoenbaum’s Shakespeare’s Lives, a long, fascinating look at all the attempts that have been made over the last 400 years to write a biography of Shakespeare.
There is no biography of Milton on the list, and there should be. The two best ones are Milton: A Biography, by William Riley Parker (two volumes, the life and Parker’s notes) and Barbara K. Lewalski, The Life of John Milton: A Critical Biography. Parker’s book long stood as the definitive one-volume study of the poet; Lewalski’s book is now considered the standard life by many (if not most) admirers of Milton’s poetry.
Shakespeare, Milton, and Chaucer: Shakespeare may still occupy the throne of literary accomplishment in English, and Milton may still stand to the right of that throne, but Chaucer–who saw all the things in English life that playwrights, poets, and novelists have been writing about since–is up there, too, and he deserves his place. John Gardner’s quirky and eccentric The Life and Times of Chaucer is nonetheless very good; and Derek Brewer’s Chaucer and His World is beautifully illustrated.