I'm following up on this as I had to go to StackOverflow to get a clue how to answer this. So, if anyone else comes along and has the same problem, here is the answer (as best as I can describe it).
The note on page 113 that Map[K,V] is a monoid if V is a monoid is a bit misleading (at least it was to me). I assumed that this was true due to something intrinsic about Map or some automatically available implicit I was unaware of. It turns out that the author's code base provides an implementation of Map[K,V] (it actually provides two of them). The implementation of this monoid is just not discussed in the text of the book. I was staring at the text of the book and trying to make sense of what I was reading and couldn't do it because I didn't have all the information I needed.
Going back to the text on page 113 I see the statement that "you need to first define Monoid[Map[K,V]] and then..." I didn't pick up on the fact that this was the only mention of this definition the author was going to make and thought it was somehow provided in the listing below it. That was where I got lost. I didn't see how this monoid was being defined in the code in the book. I was right, it wasn't. It was defined elsewhere. I just didn't know where to go to find it.
If you are interested it is in the code for chapter 4 in the patterns/monoids/foldable/Monoid.scala and patterns/monoids/monoid/Monoid.scala files.
