Sorry to ask a question and run like that! We have several correct answers, and some that I think are correct but need seconding by someone:
Correct answers:
Mickey on top of the spire in the front of the park (ADaddy)
Topiary Mickey close to the Brown Derby (ADaddy)
Wooden one at the end of the Animation Tour (MBabe)
Mickeys in the preshow/museum at One Man's Dream (ADaddy)
Muppetvision 3D (Pooh&Piglet)....this wasn't on my list, but it's a pretty creative answer and does match the question. Good enough for me!
Need confirmation:
"In the courtyard around the hat." I'm not aware of any, but if there are some someone needs to confirm.
"several other Mickeys in and around the Fantasmic theater"....I am not sure there are. I don't recall seeing any, and will need confirmation on this.
"Does the one the little girl is holding in ToT count?" No, MBabe, though it's a lovely try.
There's one more that I can think of. He's in full color, and not hidden!