Hi John,
The top of the Portspoof lab lists http://portspoof.org/ as the website for Portspoof. This leads to a defunct Wordpress site.
http://drk1wi.github.io/portspoof/ is the correct website. Alternatively, you could link to the Github page for Portspoof: https://github.com/drk1wi/portspoof
Current lab page:

Portspoof.org:

Portspoof Github.io:
