How do I know if I have pppd installed?

[Brian Benson <bmbenson earthlink net>]

I am trying to get my computer to dial out to my ISP.  It seems that I need
this thing called "pppd" and  I don't know whether or not I have pppd
installed.  I can type "pppd" at the command line and get no error, but
when I try to follow the directions to set it up (from the Linux PPP
HOWTO:) I don't have files where it says that I should.

How do I know if I have pppd installed?

Thanks,

BB