Hey hey,
If you don't mind working directly with roff commands,
you can just use an existing man page source as as
starting point.
If you like markdown, here is a project that converts
markdown to man page. Punning on 'roff', it is called 'ronn'.
http://rtomayko.github.io/ronn/
When I write man pages I use pod, a simple markup originally
created for writing man pages for perl programs. Pod can be
converted to roff, html, texinfo, latex, ascii and other
formats. In contrast with markdown, the text style is
giving by a letter followed by text in angle brackers, for
example, B<bold text>.
Happy authoring!
--
Joel Roth