I have just discovered via another Rootschat post, that if you access google books (which you do by clicking on "more" which is on the same bar as "images", "maps" etc, then clicking "books") and you put in your ancestor's name, location etc, you will get a list of publications with that word in. These publications include magazines, papers, books etc. You may then be able to read a relevant article. This afternoon, I found a death notice from 1818 for my 5xgt grandfather, a vicar, with reference to his son "a French Teacher in Carlisle"!!! See how useful it could be.
Daisy Loo, this is similar to the information you can sometimes find on the Gale Newspaper archive mentioned above - put more or less anything in and search and you'll see what I mean.