Genealogy / THE MEANING AND RESEARCH OF MY POLISH LAST NAME, SURNAME? [4500]

[Moved from]: Przytula - Question about birth document?

My father lived in Dubno, Wolin - used to be in Poland now Ukraine
The question would be : if I would like to find some birth document - parents.. do I need to go to Poland or now in Ukraine ?

Because my name is very common in Poland, I would like to find out if there are still relatives alive ?
I live in Belgium
Thanks for all reply/help
best regards, Zbigniew Przytula (the l should be the polish character, but my keyboard does not support this..)