\newcommand\myCommand{do nothing}
this is not the default in LaTeX, but no real error. Write always
\newcommand{\myCommand}{do nothing}
and all works well.
\usepackage{html}
which is part of your local TeX-Installation or available at CTAN!and in the text write
\htmladdnormallink{Go to TUG}{http://www.tug.org/Where_Else}
\htmladdnormallink{email for you} {mailto:hvoss@perce.de}
For other options and commands look at the html-style file.