Maryann,
Not my thing, clearly, and yet there are lots of these. The usual candidates like Tintern Abbey and Dover Beach, but don't forget the outliers, like
Hymn to Prosepine. Not in IP, of course, but a monologue nonetheless. I think the speaker is meant to be Julian. Oh, and, the blessed damozel (also not in IP) ...
More as I think of them,
Thanks,
Bill
(editing in, after having reread your question: you may wish to look at some of the poems in James Wright's Shall We Gather at the River. I wouldn't exactly call them DMs, but many are in IP, in contemporary speech, and they are certainly monologues...
Hmmm... may have gotten the book wrong. Try this:
http://www.poetryfoundation.org/arch....html?id=16968
http://www.poetryfoundation.org/arch...html?id=173010
http://www.poetryfoundation.org/arch...html?id=171354
This one's fun:
http://www.poetryfoundation.org/arch...html?id=237188