Madeleine Brent, I don't know if she(he actually, since it is a pseudonym for Peter Odonnell?) is available in ebook format. Have you read any Elizabeth Peters? Her character Amelia Peabody is a turn of the century archaeologist. Elizabeth Peters also writes under the Barbara Michaels name. Stirring the cobwebs of my reading past by doing a search I found several more authors in that vein that I used to read
Edwina Marlow
Mary Roberts Rinehart
Barbara Wood
Anya Seton
Anne Maybury
I just recently finished reading Elizabeth Kostova's The Historian which is definitely a literary Gothic take on Dracula. I enjoyed it.
More modern style equivalents authors could be Mary Higgins Clark?