In my 2002 posting I assumed at least three different roots of the Buder surname, among them the Slavic "bud-".
This last assumpion is supported by the German surnames database http://ahnenforschung.net/cgi-bin/mdbase/mdb.cgi?db=nachname...
saying that the surname Buder is derived from the North and Eastern Sorbian profession name "budar" meaning "owner of a "Bude" (hut, dwelling). Sorbian is a Western Slavic language spoken in Upper and Lower Lusatia in the German Länder of Saxony and Brandenburg.
On another note: my e-mail address has changed, see above.