Al, I may be able to help you with this. If the text includes the page numbers and footnotes using one of the standard DP markup schemes, I can convert that automatically into better page numbers and footnotes, and we may be able to handle cross-references the same way I do with Encyclopedia Britannica. The text errors still need someone with an editor, of course.
As an extreme example, I've got an errata report on my hands that's 3400 lines long, that I haven't had the courage to plow through yet. The reporter lists something wrong on almost every one of the book's nearly 400 pages. On top of that, he'd like an HTML version created with the footnotes cross-linked and from what I can tell, the page numbers inserted because there are internal references to them. The reported-on text is one volume of a series, so fixing/reposting it will take it out of sync with the rest. Probably simpler to figure out the source edition and run the whole series through DP, to replace the current files.