I would strongly encourage you to go electronic. There are probably at least 5 to 10 Apps and websites that make finding campsite extremely easy compared to leafing through a bound guide book. I suspect once you get used to doing that the book guides for campgrounds would be tossed out real fast.
For example, right now on this netbook I can fire up MS Street & Trips and open a map with nearly every private (paid) campground in the country shown by little yellow dots (my color choice). Or on another map I have every public campground shown the same way. (Or they could be merged into one map).
As we are riding down the road all those campgrounds appear out ahead of us all day.
And S & T is just one of many ways of doing this. I'm sure others have similar and probably better ways of finding campgrounds
At least give it a try. I think you'll love it.