If you swipe in from the left, then abruptly change direction and swipe off the left side, you'll see the app-switching bar listing all currently running Windows 8 apps. You can select any of them by touching the peek icon. Note that desktop apps are simply shown as a single representation of the Windows desktop, even if you have multiple desktop apps running.

The modern context menu (akin to the right-click menu on the desktop) is now a bar at the bottom. You bring up the Windows 8 context menu by swiping up. The context settings available will vary depending on the application.

Pinch-to-zoom will give you a miniature view of all the items on the Start screen, scaled to fit on a single display. Poking any app tile will return you to a normal scale view.

All of this mousing around may seem tiring, so you may want to consider using basic keyboard shortcuts for easier navigation. I won't list all the shortcuts, but here are some popular ones that ease navigation chores. Most involve pressing the Windows key plus some other key.