my blogs have gone!! server issue?

Hi
I recently set up two blogs using wp3.0 and everything was fine.
I changed the indexing on my host directories and since then they haven’t work… I changed the settings back and got my host to check their end but they seem confused as they keep going on about an empty folder – it was empty before and I wasn’t using it for wordpress anyway.

I can now get into the main admin part but when I click on either of the extra sites I made it says they don’t exist yet they are still listed.
I tried making a new site but that doesn’t work either – I can’t remember the error message and I can’t log in at the moment… I’ll have to check later and I’ll post that up.

Not Found
The requested URL /blog/lenny was not found on this server. is the message i get when I try to look up one of the blogs.

I guess I’m going to have to delete everything and start again.