When you record video with an iPhone 3gs and then backup using iTunes where are those video file stored? I'm trying to retrieve some lost files.
Which version of iPhone OS are you using?
It's only since 3.0 that videos are backed up. And since 3.1 it won't back up videos over 2gb.
More info from Apple KB
From that same article:
It looks like if you've backed up the iPhone since losing/removing the videos from the device they won't be in the backup.
In XP the backup is stored at: