If you're looking for a site that's comprised solely of reviews, try one of my faves: www.hollywoodbitchslap.com
Or here's a site I just discovered through a Google search: http://www.robinsweb.com/70s/70's_tv_movies.html
If you're looking for something specific, maybe you could share what you're looking for.
Hope those help a bit.
You might try www.boxoffice.com it's the web site of Boxoffice magazine a trade paper for theatre operators. They have "classic" reviews going back to the '20s.