Yay! I just found a copy of macpix.sit.hqx! A free pascal interpreter for mac (by the people who did Dr.Pascal) that's mentioned in my copy of Pascal-An Introduction to the Art and Science of Programming by Walter J. Savitch.

http://www.it.jcu.edu.au/Subjects/cp1300/1996/progs/ - files for Pascal, 5th edition by Addison-Welsey, 1995 (This is where I found it.)

Now if only I could find the rest of the files that were for the book.

LIst of files for the book.