The Period Movie Review - A very informative site dedicated to historical films with a special eye to costume dramas. Regularly updated movie reviews along with wonderful screenshots and in depth commentary on period costumes.
Enchanted Serenity of Period Films - Another good blog about period films. Lots of attention is given to period actors and recent period drama news and developments.
Costume Drama Reviews - A great blog with original and insightful reviews on the latest costume dramas. Focused mainly on classic literature film adaptations.
Just Period Drama - Centered around Jane Austen period dramas. Includes some fun little quizzes and polls.
Long Ago Captures - Great information on upcoming historical movies along with regular commentary on period actors. The screen captures section is a feast for the eyes.
The Costume Chronicles - A webzine publication with insightful and original writing on fashion, costumes, period dramas, and period literature.