desperate help needed any ideas?? please help

i bought a new intel imac 2 weeks ago.
today i restarted my computer and found all my music gone and my pictures gone none of my system prefrences where there etc. it was almost like a semi fresh install. half was gone but half of my programs and work was still here. i searched with spotlight for stuff that was missing and it cant find it

any ideas how this has happened is my stuff still here??

please help

Maybe you can access them if you sign on as the administrator.

Or maybe you need to call Apple. But that sounds weird.

call apple. dont use it as this could over write your files that you may have 'lost'

chris tm