Sometimes, it helps to actually read the error messages instead of pasting them here.

You probably have a repository configured where this package is not available. Use another repository.

Out of curiosity i entered "quilt ubuntu download" in google (ok, this was a really far-fetched idea, i have to admit - nobody else would have found that) and found some gazillions of hits, of which the second one was this:

Ubuntu -- Details of package quilt in hardy

At the end of the page the big fat link "download quilt" is hard to see.

I hope this helps.

bakunin