I'll give just a few tips here on how to do this, it's not terribly hard.
It's easier to go around the edges with the eraser than to use the "magic scissors".
Don't resize the image until you're otherwise done.
Don't crop it until after you resize. Otherwise you'll have your drop-shadow cropped off.
The coolest thing about this photo is that Noah was my photographer. He was not quite 3 years old at the time.