The last "unspoiled" version of the Kernel HOWTO (Linuxdoc source SGML) can be downloaded from our CVS repository here.
Kwan Lowe is writing the replacement, which is more or less finished and browsable from http://www.digitalhermit.com/~kwan/kernel.html. Kwan changed the name to Kernel Rebuild Guide.
Brian Ward, the original author of the Kernel HOWTO, plans to release an alternative document, for the new kernel.