Many thousands of people each month are looking for this website, and there aren't many searches comparitively, so I thought this deserved a mention. The website is: http://www.reserveamerica.com/
I can see why many people are looking for this website in particular. It has a lot of good information about where to go when camping. There isn't just RV camping, there is also: tent camping, trailer, group sites, day sites, boat sites, horse sites. You can choose any state of the continental USA plus Alaska. You can also choose a park name or zip code/city near which you want to stay. You can even choose the dates you want to stay to find out if that place is available when you want it. OH MY! It even gives you the option to choose what size site you want, with certain hookups, whether you need a pet-friendly place, if you want to be near a water, near hiking/biking/fishing/hunting, winter activities, equipment rental places, golf, horse-back riding. Unfortunately, I didn't see an option for Wi-Fi camping spots. Overall, however, this part of the site is the most extensive of all I've researched.
WOW! The map is also more extensive than the other websites I've researched as well. There are little green dots where on the map the campsites of which they have information are located. That's quite a nice feature - then if you know roughly where in each state on the map you are staying, you can see how many campsites are nearby.
The next blue tab at the top of the screen has spotlights, and it looks like most states are included. There is a little blurb and picture of all of the campsites recommended. I thought I'd just see a few sites included, but, no, there are many campsites all around the nation included. I can tell that many hours went into research (or maybe these places are where the website staff have stayed and enjoyed).
The next tab is where you can find outdoor gear, and also some jobs through Monster. That's nice and handy if you forgot some important gear.
In the next tab, it takes you to links for Hunting and Fishing Licences in each state. That's very useful and informational. It's sortof like they thought of everything needed to have a good camping trip and included it into their site.
The last tab is where you can include an account and reserve campspots. Again, the URL is: http://www.reserveamerica.com/
I highly urge you to go to this site the next time you want to look for any type of camp spot.