Windows Vista Missing Emails in Outlook 2007

[wahn]

I have received a number of really important emails, left them in outlook or put them into the deleted folder. There are a number of emails no longer in my inbox which the Outlook 07 find option however cant locate! Should I perhaps look through my archived messages? is there a way to search archived emails w/out restoring them? I know exactly the email address of the email sending whose message I am looking for but I cant find it!