I don't know of anything that specialized. I've always had to research the RV parks and campgrounds independent of my general travel planning (which I used to do with Streets and Trips, rather than a web-based resource). S&T did have the Woodall's database of locations included, and linked online to the Woodall's directory.
Woodall's and Trailer Life RV park and campground directories have been replaced by the Good Sams directory, contents of which are linked to the Good Sams travel planning tool. But you may still need to click on each park or campground, to find the information about it.
