[Ger-Poland-Volhynia] Germany, Russia locations 1860 - 1905

[Charlotte Gorley]

I'm hoping someone can help me pinpoint some locations.
 
One line in my genealogy research has references to this location:
Jannivitz
Jannowitz, Lukon, near Schlawe, Pommern
Jannetitz, Kreis Schlawe, Pomerania, Prussia
I'm not sure which one is correct and would like clarification.  The
timeframe I am looking at is 1880 - 1905.
I'm also interested in locating Plotzig, Kreis Rummelsburg, Pomerania.
My ancestors gave their ethnicity as German when the immigrated to Canada in
1905.
 
The other line I am researching in the same timeframe is Kurowek, which I
believe was/is about 45K southwest of Lodz.  I believe a that time it was
considered Russian because Poland did not achieve independence until after
WWI.  These ancestors gave their ethnicity as Russland (Russian?) on the
passenger list.
 
One other place is Dunzick, Germany in the 1860s.
 
I would appreciate being able to place these on a map for that time as well
as a modern day map and the coordinates (latitude, longitude) would be much
appreciated.
 
I am also interested in contacting someone in those locations who could help
me with some family history research.
 
Thanks for your help,
Charlotte