DrSentenial has shared some great piano tutorials in the past and is back with more. These videos are a very helpful resource if you're trying to learn to play pony songs yourself.
This time around, he's shared tutorials for Smile and for This Day Aria. You can watch DrSentenial play Smile in the video at right (it sounds awesome!), then watch the tutorial here. Listen to This Day Aria here, then check out the tutorial.
Zeke2d also wrote a transcription based on DrSentenial's tutorial for At the Gala, which is another super cool music resource. Find that sheet music here.