Sometime ago I started a project with FamilyTree DNA. I got really busy and didn't pursue it as much as I wanted. However it is back in the swing now. We have 10 people who have tested and it shows 9 different groups so far. DNA testing can really be the breakthrough you are looking for. We have a temporary web site :http://www.familytreedna.com/public/Kastner
During the next month another web site will be up and running, giving even more details.
If you are a male with any of the variant Kastner spellings, please consider joining. It is a simple swab to your cheek, no blood test. If you are a femail and would like to contribute to a general fund for Kastner,s you may do so at the web page. It is administered by FamilyTree DNA. If you have questions, please contact me.