I"m having real issues with this OS upgrade. everything is gone or moved. iphoto, itunes, imovies, etc are all missing my content. Where did it go?
You have supplied no information about your Mac or how or what you installed, To and From.
Your data will still be safe on the backup you made before you made the decision to upgrade, luckily. So if you have installed wrong, then that backup will be vital.
->System Preferences->Users & Groups and see if you have another account.
See if this article helps:
Retrieving data ...