Fashion Era, based out of the UK, is a site that "looks at women's costume and fashion history and analyses the mood of an era" such as changes in culture, technology and values. The site traces fashion, cosmetics and costume back approximately 200 years, from the Regency period to today in detail, analyzing all types of clothes, from children to adult, every day to formal, social class, etc. Fashion Era also has a page especially for petites, which includes commentary on what "petite" is, why petite sizes are needed, plus-petite problems as well as examples of "on the edge of petite," which the writer, Pauline, uses her 5'9" niece and herself as examples. Her niece, who would normally shop at tall stores, has a very short arms (for her height, especially) and narrow shoulders. She buys petite tops. Pauline, who is borderline petite-average (just under 5'4") has super-long legs. She says she often shops for longer length pants (I guess pants in the UK are shorter? I define "long" as 36"...someone who is 5'4" with a 35"-36" inseam would be really out of proportion) because they fit better at the knees, even if she has to take an inch off of them. She also advises that one needs to understand her body and figure, and in order to do so, one needs to try on a wide variety of styles.
Fashion Era is a great site not only for advice on what's in and what's out, regardless of size, but also for those of us involved in theatre who're looking for costume advice as well as those in history or sociology, looking at how fashion impacted history and culture (or how history and culture impacted fashion...totally a chicken and egg situation here.)