I had a bunch of errors in the output of sudo apt-get update: duplicate entries and 404 not found errors.

Figured those out, I hope: I removed PPAs that didn't have any packages associated with them, then I removed out a duplicate entry in `/etc/apt/sources.list`.

It seems I have royally buggered it up. Now most of the lines say *Ign* when I do `sudo apt-get update`.

How do I go about straightening out what I have screwed up? I need to get rid of these `Ign`s that are all over the place. There are about 50% (eyeball guess) `Ign`s!