Some of the names can be found in Czech Republic and Slovak Republic .
I did find a ZAVACKY listings in the city of Praha, Czech Republic.
Our ancestors call themselves Bohemian or Moravian as the Czechoslovakia did not come to existence until after 1918.
In 1993, Czechoslovakia became Czech Republic and Slovak Republic.
Have you looked in the Ellis Island web site for the name?
What religion was this St. John Church?
The name ZAVACKY can also be found in the Eastern region of Slovak Republic in area code 56-Michalovce, Koromla, Vinne, Humenne, Rokytovce, Kosice, Mikova, Stropkov, Bardejov, Svidnik, Spisska Nova Ves, Smizany, Levoca, Hnilcik. Very important to establish a village that they came from.www.zoznamst.sk
Slovak phone book www.our-slovakia.comwww.village.skwww.hosmanek.com/slovakhttp://feefhs.org/slovak/frg-slrp.htmlwww.mapy.atlas.sk
The Czech phone book is at http://phone.quick.czwww.mapy.atlas.czhttp://mesta.obce.cz