I’ve just recently learnt of a wonderful online resource; Nancy S. Weyant has compiled a comprehensive lists of works and essays published from 2002 onwards relating to Elizabeth Gaskell, from biographic works, literary criticisms, her correspondence, to Masters and Honors theses. It’s available in PDF format on her website.
She’s also published a reference book titled: Elizabeth Gaskell, An Annotated Guide to English Language Sources Published 1992 – 2001
A great deal has been written about Elizabeth Gaskell in the last decade. This extensively annotated guide to the literature builds upon Weyant’s 1994 work on Gaskell that covered some 350 sources published between 1976-1991. This supplement identifies almost 600 new books, book chapters, journal articles, dissertations, masters theses and honors theses on the life and writings of Gaskell published since 1991.