I upgraded my iPad to iOS 6. Now all my apps appear to be gone. Am I missing something? Have they moved to a new place? How do I get them back?
(I don't sync my iPad to a computer, if that is relevant.)
If you don't have a backup somewhere (on a computer or in iCloud) you must download all apps again from the App Store.
For the next time go to Settings > iCloud > Storage (in the bottom) > Turn on iCloud-backup.
You should not have lost your apps if you upgraded from iOS 5 to iOS 6. Are you sure they weren't moved to a different page on your home screen? Did you go from iOS 4 to iOS 6?
If they truly are gone, you can easily get a list of all your previously purchased/downloaded apps by going to the App Store, then the "Updates" tab, then by tapping on "Purchased".