There has been a link to his website from the Making of Mink Car module on tmbg.com since its creation, and there is also an easter egg to his website on the tmbg.com Venue Songs page. Your PC's resolution needs to be at least 1024x768. If you maximize your web browser, you will see a small block cut out of the background stripe in the top right. Click it, and you'll be taken to his site.
The 403 error pages on tmbg.com used to all link to his website, grodzki.com.