You should find it in the all apps screens, bottom left of the start screen in metro will take you to the all apps. If I remember right it should be with xbox games and you may find it if you have the xbox tile on the start.
Updates
Hi just updated to 8.1 without a problem and it was quick. Checked the drive afterwards and it is showing windows old folder. Disk clean up is showing 4.5 gig of win 8 can be cleaned.
Then checked win update and there are 5 updates to download. Bing as an optional one and one is the...