I've been to Gratefulfest many times, and to other festivals there as well. By all means, GO! It's a great place!
Camping is "primitive" - and will be very cramped early on, but all the sites are in the woods, so they are shady and level. Latrines are available, and the last year or two they started having "shower trucks" available. There is a wide variety of food available on site from many vendors, but you may also bring your own cooking gear / firewood, etc. You may NOT cut wood there at the venue. Also, NO GLASS containers allowed.
There is an awesome spring fed quarry with a beach ( and a cliff dive! ) there for swimming. You may also take kayaks, canoes, etc. The water is very clean.
Outside of that, a nice playground for the kiddies, basketball courts, and other amenities. They do sell ice on site. One super nice thing about it is that the park is private property - so the police aren't there unless there is a reason to call them. Therefore, things are very chill and low key about any recreational activities you may wish to indulge in. However, be forewarned that serious foolishness is only tolerated to a certain extent, and if they spot any hard drug use or sales, you can expect to become a guest of the local sheriff.
If you haven't checked out their website, it's www.nlqp.com
. Go, you will love the place - I've never heard anyone have a bad word about it.