Can anyone tell me what:

"the path to the sendmail (on *nix) binary on the bigbluehost web server"

is?

I am referencing the following tutorial recommended by pershoot from a previous enquiry:

http://www.stargeek.com/php_email_tutorial.php

Log in to CPANEL, left hand side, "General Server Information".

Perl and sendmail paths are currently

perl /usr/bin/perl

Sendmail Path: /usr/sbin/sendmail

This will change as we add servers always best to log in to cpanel
http://www.yoursite.com/cpanel

and check
rd