That’s about half the price at Amazon and an amazing deal if you don’t care about getting the packaging and disk and all that stuff.
To get the Mac App store, click on the Apple icon on the top-right hand corner of the desktop, and run software update. Installing the latest update will give you the Mac Store App, which pops up in your applications dock on the bottom of your screen.
Also on the App store:
Pixelmator for $29.99 (a simply AMAZING Photoshop-like editing program that I highly recommend)