I assume you are referring to Eichhorn (with 2 "h"s near Zistersdorf in the Province of Lower Austria (Niederösterreich). If so, your posting should be on the Lower Austria Board:http://cgi.rootsweb.com/~genbbs/genbbs.cgi/Austria/LowerAust...
There are also 2 Olbersdorfs in Lower Austria, one is near Hollabrunn -- the other near Thomasberg. See:http://www.rootsweb.com/~autwgw/agsfrpf.htm
If you require birth/marriage/death records you need to contact the respective parish directly.
Re possible living descendants: I am sending you a separate e-mail with listings from the current phone directory. See:http://www.rootsweb.com/~autwgw/agsfre.htm