That was Antonio (don't remember his last name) and his site was classicd&d.com, but it appears to be gone now. Too bad. I do have a .pdf I downloaded though that takes the Action Checks through to Level 36. Check your e-mail for a copy.
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You can find it here on DF: http://www.dragonsfoot.org/forums/viewtopic.php?t=18362
Thanks for the info, guys!