Camping Blogger has a series of excellent posts for those planning future adventures in the USA.
The Internet has been a real boon for people trying to find campgrounds with open campsites available. Online reservations sites, like Reserve America and
Reservations.GovRecreation.gov, allow you to find a campground by proximity to a city, town, or popular attraction. Let’s see what we can find around Monterey, California – one of the more popular destinations in Northern California, in the next two weeks. …read the rest of this post – How to Reserve a Campsite Online
New to me was the use of Google Maps to check the exact location of specific campsites.
Good idea.
Related Camping Blogger posts:
besthike.com 
Interesting. We do this for state parks, but more and more are going online.
Doh! I pooched “recreation.gov” huh? I really need to remember to get that first cup of coffee down, before I post 🙂