Need some really Unix-y help w/basic commands ...

[PoliticAverse]

1. The reason hexdump * | head -4 > <filename> didn't work...

is because it piped the output of the entire first command "hexdump *" into "head -4" not the
output of each hexdump one at a time.

You need a short shell script, like:

#!/bin/bash
for f in $*
do
echo -n $f " " >> output.txt
hexdump $f | head -4 >> output.txt
done