If these style files are not installed in one of the locations automatically searched by your installation of LATEX then they should appear in the same directory or folder as worksht.tex.
To print or view this LATEX document we first produce a ``.dvi'' file. On a command based system you would normally type a command of the form
latex worksht.tex
On an ``icon'' based system you would start the LATEX application and then use its menus to ``open'' the file ``worksht.tex''.
Finally, the resulting file ``worksht.dvi'' is then processed by another application such as ``dvips'' to send the document to the printer or to preview it on your screen.