If you are only interested in the first occurence of a pattern, you can use
something like
sed -n '/<pattern>/ {
p
q
}' file
Harald Schaefer
Siemens Corp. - RTL
Bus. Phone (609) 734 3389
Home Phone (609) 275 1356
uucp: ...!princeton!gypsy!hasch
hasch at gypsy.uucp
ARPA: hasch at siemems.com
hasch%siemens at princeton.EDU