Restore Lost All of My Contacts, Pictures, etc.

I have an iPhone 4S that was running on iOS 5.1.1. I decided to update it to iOS 6.1. So I went to Settings, General, Software Update, Update. When I pressed the Update button it started updating then I left it alone for a while. When I came back there was a picture of my phone with the USB connector going to an iTunes symbol, this was on a black background. So I hooked up the phone to my computer and started up iTunes. It said that the phone needed a computer to update. So I click update and it gives me an error, saying that I need to restore my phone. I restored my phone and now all my data is gone. I did a backup of everything around Christmas but I can't find it on iTunes. How can I get all my contacts, pictures, notes, texts, reminders back? Please help me.