Yeah, there are files on eab's ftp servers. Amiga -> Misc. Use Cammy's image as filedisk 1 and boot into that and install or just use that. Macintoshgarden hosts mac rom's (I think). Make sure you use something appropriate!
I've been struggling with ShapeShifter many times. I'll do my best to assist! You might want to delete your pram-file (in Shapeshifters directory) and see if it fixes your "smiling-mac" error.
What is your OS?