/my/web/root> tar -cvzf mywebroot.tar.gz *.html
Note the new option (z) and the new file extention (.tar.gz)
The ability to create zipped tar files is a handy convenience, otherwise you would find yourself zipping up the tar files in an extra step. It's just easier to do it this way.
To view the contents of a zipped tar file is just as easy:
/my/web/root> tar -tzvf mywebroot.tar.gz
Give it a try!