what happened and how do i get it all back ? ( redownload or something else ?)
Do you mean avast icon?
Which database?
Which is your Windows? XP? Vista?
Can you try to repair your avast installation?
Go to Control Panel > Add/Remove programs > avast! antivirus > Remove. Then choose Repair function in the popup window (Repair).
If this does not help, can you uninstall / boot / install / boot again?