I can't find that pixel, and would like to have him... someone help me find him!!!

What it was?

I think it was the musical note, isn't it?

You need to go to flop side... it's behind the house locked with a key.

If you do not have the key, you need to go to flipside and go to then psychic guy. jump over his crytal ball and he will start explaining to you some personal needs he have... then you will need to go throughout the stages to help some people and at the end of this quest, you will receive the key.

http://www.cheatscodesguides.com/wii...-paper-mario-/
Go to this website and it's towards the top. There is a bunch of steps you have to follow I'm about to go try it soon.