Thanks for telling me about freebmd.org.uk. I've never heard of it before.
I had already found a few UK documents and censuses for my grandfather in the UK (I'm subscribed to Ancestry). Israel (Gerald) was my father but he knew almost nothing about his father's life and family in Poland. It's the Polish records that I can't find for him or any other members of his family. I had hoped to find his grave on Findagrave or Billiongraves because that would tell me his and his father's Hebrew names which might give a clue to the names they used in Poland. But it is not listed (yet). Do you know of any other documents where I might be able to get this sort of information?
