Second using Google maps. I have Google maps open in two tabs. The first tab with the route and I will use it to find the area that I will be staying at and then in the second will zoom in on that area and search in Google maps for RV parks. Then check them out in RVparkreviewa.com.
BIG suggestion with the time of year and the country that you will be traveling in get a weather radio with travel mode. Second if there is the least bit of chance of bad weather ask the campground people where they suggest to take shelter.