My name is Mark Zelasko, and I know most of the Zelaskos in Illinois. My father is Gary, grandfather is Raymond, great grandfather is Victor, and great great grandfather was Frank.
Hopefully, I can help fill in the gaps. My grandfather on the other side of my family did very extensive genealogy on his side and some on the Zelasko side too. I don't have all of this info handy, but I'm sure I can get ahold of it.
Feel free to send me an email, and we'll see what we can put firstname.lastname@example.org