If you have problems or suggestions regarding this document, you should probably submit them as a bug report against the package debian-installer-manual. See the reportbug package or read the online documentation of the Debian Bug Tracking System. It would be nice if you could check the open bugs against debian-installer-manual to see whether your problem has already been reported. If so, you can supply additional corroboration or helpful information to <XXXX@bugs.debian.org>, where XXXX is the number for the already-reported bug.
Better yet, get a copy of the DocBook source for this document, and produce patches against it. The DocBook source can be found at the debian-installer WebSVN. If you're not familiar with DocBook, don't worry: there is a simple cheatsheet in the manuals directory that will get you started. It's like html, but oriented towards the meaning of the text rather than the presentation. Patches submitted to the debian-boot mailing list (see below) are welcomed. For instructions on how to check out the sources via SVN, see README from the source root directory.
Please do not contact the authors of this document directly. There is also a discussion list for debian-installer, which includes discussions of this manual. The mailing list is <debian-boot@lists.debian.org>. Instructions for subscribing to this list can be found at the Debian Mailing List Subscription page; or you can browse the Debian Mailing List Archives online.