I had exactly the same experience (minus reading the book). Often, I'd just see the function signature and no further explanation. I do realise that it takes a lot of time and effort to build up extensive docs, but it happened enough that I put it down and started looking for another Lisp that compiles down to a binary.
I'm curious, which Lisp did you end up choosing?
I'm still looking around, but Owl is a frontrunner.
If the bigger runtime isn't a deal breaker, maybe look at Racket.