Autotoolset is both a colection of small tools (scripts, emacs macros, etc.) to simplify project development with autoconf/automake/libtool/texinfo/emacs and a good documentation on how to get started on these tools and the whole GNU software model.
elmake is a way to provide makefiles for elisp packages (for emacs) which are processed completely in Elisp (no external autoconf, make etc. required). For info files, an external makeinfo is suggested, as elisp parsing of info files is slow.