Although the Woggle-Bug comes from Oz, and this book is therefore often listed in the canon of Baum-authored Oz books (bringing the total from 14 to 15), it is much shorter than any of the others and for the most part does not take place in Oz.
But there's another reason many Baum aficionados don't want it to have a place in the canon: there's some crude racial humor in it: Arabs, Chinese, Blacks, etc. Get ready for the N-word, for example. This was quite par for the course in the early 1900s, but Baum fans wish this book would just crawl back into a cave.
The plot is thin as gruel: it concerns the pretentious Woggle-Bug being abruptly transplanted in modern Boston and being seized with a jonesin' for a plaid dress. He follows his dress around from wearer to wearer. Not very interesting. My suspicion is that the author thought up a splendid name for his character but didn't have much else: a title in search of a plot, in other words.
By the way, the copyright on this has long since expired, so you can get the text for free anywhere on the internet. Which leads to the question of why you're buying this: it's text only. There are no pictures.