Jim, I think the reason you cannot locate Belmont is that at some point in the 1800s (I think), the original old town of Belmont was absobed by Sardis. In fact, the town of Belmont was first called Danville for Dan Killebrew, the first school teacher in the town. W.H. Alexander who kept the first store and also served as the first postmaser gave the town the name Sardis, choosing the name from one of the seven churches named in the Bible in the Book of Revelation.

You might look at http://en.wikipedia.org/wiki/Panola_County,_Mississippi where you will find the following:

Two of the oldest settlements in the county were at Belmont and Panola, a few miles apart, and on opposite sides of the Tallahatchie River. For several years there was a spirited contest between these two towns over the location of the courthouse of Panola County. With the advent of the Mississippi and Tennessee (now the Illinois Central railroad) Belmont was absorbed by Sardis, and Panola was absorbed by Batesville. One result of the above contest is found in the two judicial districts of the county, Sardis being the seat of justice for the first judicial district, and Batesville for the second judicial district into which the county is divided.

So, I guess the answer to your question is Belmont was located where Sardis is located now.

Hope this helps.