[X4U] iPhoto library not found

[Neil]

All of a sudden, every time I try to launch iPhoto it tells me that my
iPhoto library wasn't found.  As far as I know, that library should be on my
startup drive.  I'm pretty sure I haven't moved it nor deleted it.  I ran
Disk Utility's repair permissions twice, but that didn't help.  I selected
the "find" button in the error message, but the files that look like
candidates are all greyed out.  In particular, I went to ~/pictures/iPhoto
library/albums/photo library, but that was grey.  Does anybody have any
ideas?  Thanks,

Neil