Poking around at Google this evening, I came across a new tool being previewed in Google Labs. It searches public source code. I put in a piece of the tcltk code and found a lot of old code floating around. Give it a try.
http://www.google.com/codesearch?hl=en
Michael
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Center for Social Dynamics & Complexity
Arizona State University
phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton