The Reference card (52 half-pages, for Tcl/Tk 8.0) can be found at
An attractive on-line alternative is Brian O'Hagan's Command Reference Guide .
However, it would really be useful for someone to get the source text of one of these into a currently used format and add them to the Tcl and Tk source distribution...
LV: Are you volunteering to take on the project? The original code for the quick references that I've seen is TeX, and that is not really the format to distribute with the source, IMO...