An example of a recto page with poem. Notice the decoration on both the top and the bottom of the page. Also, the poem is printed in modern English, without the archaic use of "v" that the title page and quotations use.
This is an example of a double page spread, where the decoration crosses the gutter. Notice how the vine goes all the way off the verso page and continues on the recto page.
A beautiful example of a decorated verso page with a quotation contained within the decoration. In person, these colors are much more striking, although they maintain their muted tones.
An example of some of the more complicated designs within Sonnets from the Portuguese. Although the twining of the ribbon and banner is seen elsewhere in this edition, this is the only image to feature text that is actually curved throughout the entire decoration. Also notice the interchange of "v" for "u." The title page and the decorations are the only place where Armstrong chose to use this archaic alphabet. 
Another beautifully decorated image. This is also a perfect example of text wrapping in the early 20th century. Notice, for instance, how the word "love" is actually divided in order to accommodate the flowering vines. This proves that Armstrong created the images and then added the text. 
Another lovely example of Armstrong's decorations. 
From the American Catalog, the ad lists this edition of the Sonnets for sale for $2. "D. cl." means decorated cloth. The ad also specifies other unique attributes of the edition including "floral head and tail pieces" and "full page designs."
This advertisement is for Literary News. Another turn of the century publication that advertised new releases. This blurb is much more detailed using language like "exquisite and "charm" to describe the edition. Prices range from $2 - $4, most likely due to different cover color options.
Public Opinion offers Putnam's own advertisement, giving us an idea of how Putnam distributed the book in 1902. This ad breaks down the specific pricing for different editions that refer not only to cover color, but also to the material used on the cover. It is amusing that Putnam chooses to praise their work "the work . . . of the printer and binder is of the highest order."
The New York Times published this ad, again with a very descriptive blurb to attract buyers. This is the only ad I've found that lists Helen Armstrong as the artist of the "frontispiece" although she does leave her monogram as evidence. It is also the only source that suggests the decorations were completed in watercolors, especially interesting since I could find no biographical material that listed Armstrong as skilled in watercolor. 