Jim,
There are lots of options. A lot depends on what you want to do while in the area. Pigeon Forge has the most activity and "touristy" things and the most campgrounds. Gatlinburg is the oldest part of the tourist things. I personally like the Gatlinburg area better than Pigeon Forge, but campgrounds are very limited. The national park is at the far south end of the activities, past Gatlinburg. I like to spend a good amount of time in the park. There are several campgrounds that are also inexpensive (compared to the commercial cgs), but are also hard to get, a limited on accommodations and have length limits. Most do not have electric and a 30ft limit. I don't fit.
At the far north end, closest to I-40 is Anchor Down. It is a VERY nice campground on Douglas Lake and is even reasonably priced, but very hard to get into. Booking a year out is needed to get a site. There are also some COE campgrounds on Douglas Lake. Bama Ed has stayed at one near the dam and I've driven through. It is smallish and basic, but a nice COE campground. In Sevierville there are a couple of campgrounds. Two Rivers is close to the main drag and sits on the French Broad River. Douglas Lake drains into it a few miles up stream.
In Pigeon Forge proper, River's Edge is OK. It is one of the older campgrounds. Sites are a little tight, but it has the location. The KOA is right nextdoor/behind River's Edge. It is hard to tell them apart. The DIS Meet 2 years ago was at Pine Mountain RV Park. It is small, but nice and has nice paved sites and a decent pool. It sits right on Mill Creek with sites that back up to the water. Pine Mountain is a few blocks off the main strip. It is quiet, but quick to get places.
There is also a new Margaritaville that is nice. It is up the hill behind River's Edge, so at the south end of Pigeon Forge, closest to Gatlinburg. It is a bit pricey, but has nice amenities, but little trees (literally). They were just planted a couple of years ago when it opened.
Another newer RV resort is The Legend Outdoor Resort. It is on the back road that Dollywood is on, but up closer to Sevierville. We have driven through it a couple of times. It is nice. It seems to cater to bigger rallies. Both times I drove through they had manufacturer sponsored events going on.
Let us know what kinds of things you had in mind doing while in the area and we can help narrow it down for you.
j