I have an iMac G3 (white) OS 9 - OS X 10.3.9 600MHz POWERPC 256 MB SDRAM with Panther

Last night I tried to install Microsoft Office for Mac, all I did was click on the 'install' icon................
- it seemed like nothing was happening, it didn't install.....
- then my desktop icons of saved items disappeared showing only my Hard Drive icon and the Microsoft Office for Mac icon,
- My desktop had reverted back to just the blue swirly background (which I was able to reset) - I have a '?' question mark in my dock where my mail icon should be (the little postage stamp with an eagle on it)
- and another '?' mark where my iChat icon should be
- all my 'documents' in my HD were gone (they've got to be there somewhere, I did not delete anything)
- and my three mailboxes were gone of course along with all my address book.
- I did manage to get my one ISP Earthlink mailbox reinstalled and the few emails that were in them before this happened were still there. So I am hoping that when I reinstall my other two mailboxes, the emails will reappear.

I do still have my OS 10.3.9 (and OS9 if I want to use it) and can access the internet and I can use my computer just fine....I just don't have my saved documents an the other two mailboxes.

please, please, please, please help me? What happened?

All this stuff is in my Mac somewhere, I just know it. (I hope so, anyway)