Also available at Open Library is Three Films of W.C. Fields (Faber & Faber, 1990), which includes an introduction by Brooks, "The Other Face of W. C. Fields." (That essay is included in Lulu in Hollywood.) The eBook pdf of the text may be found at http://openlibrary.org/works/OL4772458W/Three_Films_of_W.C._Fields
There are many other swell books on early film available through Open Library. be sure and check it out.