There is a hidden mickey inside of the Main Street USA Penny arcade. 

First find the Pinocchio puppet game where you can control Pinocchio as a dancing puppet. 

If you look under the words "make him dance" you will see a classic hidden mickey.

Below are some pictures of the Pinocchio game inside of the Penny Arcade that has the hidden mickey.

As you walk along Main Street USA there is a door that says Disneyland Casting Agency.

If you go up close to the door there are two classic hidden mickeys.  One hidden mickey is on the top and one hidden mickey is on the bottom of the glass portion of the door.

Both hidden mickeys are formed by the decorative border of the sign.

When you enter the Main Street Cinema look at the step the lead up the platform in the center of the room.  There will be classic hidden mickeys on each of the three steps.

Each step has 2 hidden mickeys formed by lights that are used to light up the steps.

Below are a couple of pictures of the hidden mickey lights in the Main Street Cinema.

If you go to the fruit cart on Main Street USA you will see a hidden mickey below the cart.  The classic hidden mickey is formed by the green steel bars below the cart.

This may not be visible from all angles so you may have to circle around the cart and squat down to see it.  This one is a true hidden mickey.

Here is a picture of the fruit cart hidden mickey, look between the two wheels.

Inside the Blue Ribbon Bakery if you go the consession stand there is a painting on the wall that has a cow and a basket full of fruit.

If you look at the fruit basket there is a large yellow fruit and two green limes next to it.  This forms a sideways classic hidden mickey.

I personally am not sure if this is a legitimate hidden mickey, but this one is listed in the hidden mickey book.

Below is a picture of the painting with the hidden mickey.

The Gibson Girl Ice Cream Parlor is located on Main Street USA.  Besides having really good ice cream and waffle cones they also have a hidden mickey in one of their lamps.  The lamp is located near the back and is hanging above a dining area.  The hidden mickey is formed by the large jewel and the two small jewels above it.  If you stand directly under the lamp you can see a better hidden mickey tan looking from further back.  I’m still unsure myself if this is was meant to be a hidden mickey or not, but this one is in the Hidden Mickey Book.  You be the judge.

Here’s a few pictures of the lamp with the hidden mickeys:

There are a few hidden mickeys that can be seen from the window of the Silhouette Studio.  One of more obvious ones is a classic hidden mickey in one of the small pictures.  However there is also another hidden mickey that is a lot smaller and harder to see.

If you look carefully at the large picture frame on the right you can see a classic hidden mickey in the decorations in the frames.  There is actually several different sized hidden mickeys in that frame if you look closely.

One of the hidden mickeys in Pinocchio’s Daring Journey is when you enter pleasure island.  Look out for a popcorn popper.  When you see the popcorn popper take a look at the ground with popcorn on the floor.  If you look carefully you can spot an upside-down classic hidden mickey created by a single piece of popcorn.

If you look at the Innoventions wall you can find a hidden mickey.  However, the Innovations wall moves around in a circle so the hidden mickey may be out of site.  While the wall is spinning around look out for a TV set.  On the face of the TV set you will find a classic hidden mickey.

Here are some pictures of the hidden mickey on the Innoventions wall.

In the entrance of the Big Thunder Ranch you will see a soap and water station that is used to sanitize your hands from petting the animals.

Approach the soap dispenser that is furthest to the left and look underneath it.  You will find a nice hidden mickey made of three holes in the wood.

Here are some pictures of the Big Thunder Ranch Hidden Mickey:

The classic hidden mickey is just under the soap dispenser created by a hole in the wood.

A little closer look of the classic hidden mickey holes at the Big Thunder Ranch.