This article is from the German Genealogy FAQ, by Jim Eggert EggertJ@crosswinds.net with numerous contributions by others.
Simple surname queries without any supporting information are
strongly discouraged. For most surnames, there are simply too
many individuals with the same name for a surname request to be
useful. To make success more probable, you must supply as much
information as you can, including the surname(s) and given names;
place(s) of residence (in Germany and elsewhere); dates of birth,
emigration, marriage, and death; religious affiliation; associated
family names; and any other information you may have. Include
also what sources you have consulted, successfully or not, in
your search. Be concise but informative. Make your question
clear. Use an informative subject line like this:
SCHMIDT; Neustadt i.Holstein,SCN,DEU > Boston,MA,USA; 1873-1924
Many people prefer that surnames be written in all caps to aid
visual scanning. Make your placenames unambiguous (Neustadt an der
Weinstrasse; Frankfurt am Main). Avoid imprecise dates like
"the late 1800s" (does that mean 1850-1899 or 1805-1809?).
Be advised that it is unlikely that you will find someone willing
to do extensive research for you for free unless he or she is
related to the subject of your search. However, you may receive
valuable advice that may turn your dead end into a new lead. If
you are lucky, you may find someone who is also researching along
the same lines (same family, location, event, or resource) and
then you can both profit by sharing notes.
Also, common courtesy would require that, when you receive advice
or leads, you act on them before repeating the query.
 
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