I am researching LAZARUS families. I'm descended from two brothers, Eleazer in Exeter and Lyon in Plymouth, sons of Moses and Nancy Lazarus who died 1810 and 1811. My search has widened to include early Lazarus families of Portsmouth, Birmingham, London, Dublin, Glasgow and Wales. Some families adopted the name LAWRENCE/LAURANCE/LAURENCE.
(My research is sorta turning into a one-name plus variations project.)

Apart from using one of the commercial genealogical sites, I access the Susser Archives, The Jewish Victorian, The Jewish Chronicle Archives, Jewishgen (in particular, Henry Roche's Portsmouth material), synagoguescribes and cemeteryscribes.

I'd be happy to hear from anyone doing related research.