Today, I managed to get hold of a copy of the first edition of Walton Burgess’s Five Hundred Mistakes of Daily Occurrence in Speaking, Pronouncing, and Writing the English Language, Corrected, New York. It was published in 1856, and it is, to my knowledge at least, the first American English usage guide. The text itself is can be found in Project Gutenberg, and I refer to it in my Introduction to Late Modern English (Tieken-Boon van Ostade 2009:5; Edinburgh University Press).
I’d be interested to hear if other people have written about it.
The book is also available, in pdf, in Google Books. (Thanks to Robin for this.)

The book is also in Google Books and can be downloaded as a pdf
fascinating!: “23. “I prefer the _yolk_ of an egg to the white:” the more common word is
_yelk_, with the _l_ sounded; but if _yolk_ be used, it should be
pronounced like _yoke_.”
HA!
That one caught my eye as well, but the book is filled with little nuggets like that!