Extracting From: e-mail address

Hi there,

Sorry, about this.  Kind of a newbie question.  I just need to know how I
can pass the e-mail address in the From: header onto a perl script?  I know
this is done with formail, but can't figure out how.

All I need is a way to extract the e-mail address from the From: header, and
pass it onto a perl script.

Any help would be much appreciated,
Mike Watkins