PLEASE HELP!!! Numbers lost!!

[sactown]

I was helping my friend set up her phone, and something very very strange happened and I have no idea how it happened. Here is the background: she had a nokia which had about 400 numbers on it. In order to transfer them from her nokia to the iphone, she took out the SIM card which had about 60 percent of her contacts on it and imported them onto her iphone. She then erased those numbers, and moved the remaining numbers on her nokia onto the empty SIM card and put that into the iphone and imported the rest of the numbers. She then wanted me to help her set up her email account and sync her phone with outlook. So I plugged in her phone and synced with outlook and set up her school email account via exchange. After that was done, I unplugged the phone and did a couple of other small things and somewhere in this whole process, most of the phone numbers associated with the contact got erased. The names themselves are still there, but the number are gone. Also, when I open up outlook, only 160 of the 400 contacts were transferred, and most of those numbers are also missing. The numbers that are still present in outlook are also still present on the iphone. I think the only hope that I have it to restore the iphone from a backup that was created about 5 minutes before this fiasco, but I cant figure out how to restore from an existing backup. Any suggestions and can anyone explain to me why this happened? Thanks.