where have all of my documents gone?

sorry if this question has already been addressed. i don't know anything
about computers or vista. i put my computer in sleep mode, came back hours
later and forgot that i didn't just shut it off, so i turned it off and then
on again. i sign in with my user name and find that all of my documents are
gone. how do i retrieve them? also, my laptop freezes every few hours or so,
and apparently it's a problem with vista. i don't know. i really just need to
figure out how to get my documents back. thanks.