Dr. Johnson asks, "What are some sources for the role of FORM in poetry? I've recently been delving into the history of the sonnet form, but I wonder if you could recommend some books or sections of books or articles on all sorts of poetic forms?"
Back in 1982 the composer Robert Rabinowitz asked me to write a brief essay on form to include with the program for a recital. The piece included two haiku, one of which I remember:
Form a butterfly
with time and caterpillar
For years I've thought of rereading G. Spencer Brown's Laws of Form and Charles Rosen's Sonata Forms and trying to come to a deeper understanding of form. I haven't really thought about poetic form for decades. I do have some concrete thoughts on the sonnet, though. Ezra Pound repeatedly said to write a sonnet a day for a year. I found this a very useful experiment, and I can think of no better way of learning about poetic form. I tried once for about five months and stopped. Later I did it for a full year, so I wrote over 500 sonnets in those two periods. I think I liked two of them. Of course, while doing that I read a bunch of sonnets and a bunch of other writing in iambic pentameter.
For the history of the sonnet, I suggest reading the pre-Dante Italian poets in Pound's Translations and in Confucius to cummings, as well as Pound's essays on Cavalcanti and Dante. Next, read Dante Gabriel Rossetti's translation of La Vita Nuova, Dante's early poems for Beatrice before he wrote the Commedia. (Pound suggested reading Rossetti's translation of La Vita Nuova before the Commedia, Eliot afterwards. Eliot feared one would get a too Pre-Rafaelite image of Dante if one started with the Rossetti.) The old edition of The Portable Dante with the Binyon translation of the Commedia includes the Rossetti.
Pound called Dante the second greatest literary critic after Aristotle. La Vita Nuova, in addition to including great love poems, includes Dante's own analysis of their form.
After reading lots of Cavalcanti and Dante, etc., one can move on reading the sonnets by Shakespeare, The Sonnets from the Portuguese by Elizabeth Barrett Browning and a selection of sonnets by Wyatt, Spenser, Milton, Keats, etc.
Zukofsky's wonderful A Test of Poetry doesn't talk a lot about form, but I keep rereading it and learning from it.
Pound recommends translating poems to help learn about form.
I don't feel like I've completely answered your question. Perhaps some more books or articles will creep into my mind. Most of the stuff on form I like pops up in the middle of pieces on various poets, Creeley's various discussions of Zukofsky's "A" for instance.