If iPhoto came preinstalled on your Mac, you need to accept it to your AppleID. Then you can upgrade it from the "Updates" panel at the App Store.
Have you alredy accepted the iLife Aplications?
If not:
- Double-click the App Store icon in the dock.
- Enter your Apple ID and password.
- Click Purchases.
- If you haven't previously accepted your bundled iLife applications within the Mac App Store, you should see your iLife applications appear in the Accept portion of the screen. Click Accept.
- You may be asked for your Apple ID and password once again. Your iLife applications now move to the Purchased section. These applications are part of the software that came with your Lion based computer. Your account will not be charged for them.
Regards
Léonie