nwo4life,
Here is a simple program I wrote to do exactly what you want. I programmed it for you so it runs interactively, but it is really simple and can be made to run without interaction with little effort. If you need help doing this, I can do it for ya..
#!/usr/bin/ksh
echo "Enter search string: "
read SRCHSTR
echo "Enter full path to file to search: "
read FILE
echo "How many line after do you want?: "
read NUMLINES
LINENUM=`grep -n "$SRCHSTR" $FILE | cut -f 1 -d :`
POS=0
while [ $POS -lt $NUMLINES ]
do
echo `grep -n . $FILE | grep ^\`expr $POS + $LINENUM\` | cut -f2,3,4,5,6,7 -d ":"`
POS=`expr $POS + 1`
done